Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| the sexually dimorphic nucleus of the hypothalamus contains gaba neurons in rat and man. | the sexually dimorphic nucleus of the preoptic area (sdn-poa) is the most striking structure displaying a morphological sex difference in the rat brain. a potentially homologous nucleus has been identified in the human hypothalamus. the objective of the present study was to pursue the putative homology of the rat and human sdn-poa by determining whether they express the same transmitter phenotype. we employed in situ hybridization histochemistry for gad mrna to show whether the neurons of the sd ... | 1996 | 9117390 |
| medial preoptic/anterior hypothalamic lesions induce a female-typical profile of sexual partner preference in male ferrets. | in t-maze tests given to gonadectomized ferrets treated daily with estradiol benzoate (eb), females consistently prefer to approach and interact sexually with a stud male whereas male subjects, on average, prefer an estrous female. in the present experiment this sexually allomorphic pattern of partner preference was changed in males given lesions of the medial preoptic area/anterior hypothalamus (mpoa/ah). electrolytic lesions, which caused extensive bilateral damage to the mpoa/ah, including th ... | 1996 | 9047276 |
| effects of testosterone and its metabolites on aromatase-immunoreactive cells in the quail brain: relationship with the activation of male reproductive behavior. | the enzyme aromatase converts testosterone (t) into 17 beta-estradiol and plays a pivotal role in the control of reproduction. in particular, the aromatase activity (aa) located in the preoptic area (poa) of male japanese quail is a limiting step in the activation by t of copulatory behavior. aromatase-immunoreactive (aro-ir) cells of the poa are specifically localized within the cytoarchitectonic boundaries of the medial preoptic nucleus(pom), a sexually dimorphic and steroid-sensitive structur ... | 1996 | 8603040 |
| effects of interferon-alpha on cytokine profile, t cell receptor repertoire and peptide reactivity of human allergen-specific t cells. | a large panel of t cell clones (tcc) specific for the recombinant form of poa pratensis allergen (rkbg7.2 or poa p9) were established from the peripheral blood of grass pollen-sensitive donor in the absence or presence of recombinant interferon-alpha (ifn-alpha) in bulk culture and their pattern of cytokine secretion, peptide reactivity and tcr v beta repertoire was examined. the majority of allergen-specific tcc derived in absence of ifn-alpha produced high amounts of interleukin-4 (il-4) and i ... | 1996 | 8605940 |
| the developmental increase of the at1a, but not the at1b, receptor mrna level at the preoptic area in spontaneously hypertensive rats. | to determine the possible involvement of the central angiotensin system in hypertension, the angiotensin ii type-1 receptor subtype mrna levels in the preoptic area (poa) and hypothalamus were measured by means of a reverse-transcriptase/polymerase chain reaction in spontaneously hypertensive rats (shr), and the results were then compared with the findings in age-matched normotensive wistar-kyoto rats (wky). in 4-week-old (prehypertensive stage) and 7-week-old (evolving stage) shr, the at1a and ... | 1996 | 8614262 |
| comparisons of the genomic cis-elements and coding regions in rna beta components of the hordeiviruses barley stripe mosaic virus, lychnis ringspot virus, and poa semilatent virus. | nucleotide sequences of the genomic rna beta components of hordeiviruses poa semilatent virus (pslv) and lychnis ringspot virus (lrsv) were determined. pslv and lrsv closely resemble barley stripe mosaic virus (bsmv), type hordeivirus, in the gene arrangement of their rnas beta, comprising 5'-proximal beta a (coat protein) gene and downstream triple gene block (tgb) coding for the beta b, beta c, and beta d putative transport proteins. the beta a, beta b, beta c, and beta d proteins of the three ... | 1996 | 8623558 |
| estradiol modulation of neuron loss in the medial division of medial preoptic nucleus in rats during aging. | the age-related morphological changes in the darkly stained sex-dimorphic nucleus (sdn-poa) and the lighter staining surrounding area (non-sdn-poa) within the medial division of preoptic nucleus of long-evans rats were studied. the long-term effects of estradiol benzoate (eb) on the changes were also assessed. during aging, the neuron loss in 14-(middle-age) and 22-month-old rats as well as increased pyknotic ratio of neurons in old male rats were observed in sdn-poa, but not in the non-sdn-poa. ... | 1996 | 8641597 |
| pituitary adenylate cyclase-activating polypeptide acts within the medial basal hypothalamus to inhibit prolactin and luteinizing hormone secretion. | in this study, we investigated the hypothalamic regulatory role of pituitary adenylate cyclase-activating polypeptide (pacap) in the control of lh and prl secretion. overiectomized ewes were surgically prepared with bilateral guide tubes directed at the preoptic area (poa) or medial basal hypothalamus (mbh). after recovery from surgery, pacap38 (0.1 nmol in 2.5 microliters over 1 h) or vehicle was bilaterally infused into each site in separate trials. infusion of pacap38 into the poa had no effe ... | 1996 | 8754770 |
| mutualistic fungal endophytes express a proteinase that is homologous to proteases suspected to be important in fungal pathogenicity. | many cultivated and wild grass species are hosts to mutualistic fungal endophytes. these associations are ecologically and agronomically significant, yet little is known regarding the physiological aspects of the interaction. in the poa ampla/acremonium typhinum interaction, a fungal serine proteinase, at1, is surprisingly abundant and may constitute 1 to 2% of the total leaf-sheath protein. sequence analysis of cdna and genomic clones indicates that proteinase at1 is a member of the eukaryotic ... | 1996 | 8756501 |
| gonadotropin-releasing hormone and nmda receptor gene expression and colocalization change during puberty in female rats. | during development, an increase in gonadotropin-releasing hormone (gnrh) release occurs that is critical for the initiation of puberty. this increase is attributable, at least in part, to activation of the gnrh neurosecretory system by inputs from neurotransmitters, such as glutamate, acting via nmda receptors. we examined changes in gnrh and nmda-r1 gene expression by rnase protection assay of preoptic area-anterior hypothalamic (poa-ah) dissections of female rats undergoing normal puberty or i ... | 1996 | 8757241 |
| [physical training and low-dose heparin-calcium in patients suffering from chronic obliterating arteriopathy of the lower limbs with intermittent claudication]. | in the treatment of peripheral obliterating arteriopathy (poa) physical training provides clear results in terms of increased walking autonomy; it is still not fully clear whether the positive effects of physical training can be further improved by concomitant back-up drug therapy. for this purpose 374 patients of both sexes, with a mean age of 64 years, suffering from chronic peripheral obliterating arteriopathy of the lower limbs were enrolled in a controlled open clinical trial, instructed to ... | 1996 | 8767599 |
| alpha adrenergic neurons inhibit luteinizing hormone pulse amplitude in breeding season ewes. | it is now clear that estradiol acts in the brain to inhibit lh pulse amplitude in breeding season ewes, but the neural mechanisms underlying this action of estradiol have yet to be determined. in this study, we performed four experiments to examine the role of alpha-adrenergic neurons in the control of lh pulse amplitude in the ewe. in the first experiment, implantation of the alpha-adrenergic antagonist phenoxybenzamine into the preoptic area (poa) during the follicular phase of the ovine estro ... | 1996 | 8788189 |
| the sexually dimorphic medial preoptic nucleus of quail: a key brain area mediating steroid action on male sexual behavior. | about 10 years ago, a sexually differentiated nucleus was identified in the preoptic area (poa) of the japanese quail in the course of studies analyzing the dimorphic mechanisms involved in the activation of sexual behavior. in this species, males exposed to testosterone copulate while females never show this masculine behavior. the present paper reviews anatomical, neurochemical, and functional data that have been collected since that time about the quail dimorphic nucleus. the medial preoptic ... | 1996 | 8788569 |
| endocrine correlates of partner preference behavior in rams. | we studied a unique group of rams that would not mate with estrous ewes during extensive testing for sexual behavior. the same rams courted males in preference to females in 30-min sexual preference tests and were classified as male-oriented (n = 6). we compared the following endocrine profiles: systemic steroid concentrations, the capacity of the testes to biosynthesize 17 alpha-hydroxyprogesterone and testosterone from 3h-progesterone in vitro, and the levels of brain aromatase activity (aa) i ... | 1996 | 8793066 |
| neurogenesis and cell migration into the sexually dimorphic preoptic area/anterior hypothalamus of the fetal ferret. | a sexually dimorphic male nucleus (mn) of the preoptic area/anterior hypothalamus (poa/ah), comprising large, estradiol-receptor containing neurons, is formed in male ferrets due to the action of estradiol, derived from the neural aromatization of circulating testosterone, during the last quarter of a 41-day gestation. two experiments were conducted to compare the birthdates and the migration pattern of cells into the sexually dimorphic portion of the dorsomedial poa/ah as well as the nondimorph ... | 1996 | 8807525 |
| role of interleukin-1 beta, interleukin-6 and macrophage inflammatory protein-1 beta in prostaglandin-e2-induced hyperthermia in rats. | the purpose of this study was to investigate the role of pyrogenic cytokines, such as il-1 beta, il-6 and mip-1 beta, in the mechanisms underlying the hyperthermic response of rats to central injection of pge2. thus, specific murine neutralizing antibodies against these cytokines were micro-injected directly into the anterior hypothalamic, preoptic area (ah/poa) of unrestrained rats just before intracerebroventricular injection of pge2. the significant hyperthermia induced by pge2 was markedly s ... | 1996 | 8809217 |
| photoperiodic modulation of monoamines and amino-acids involved in the control of prolactin and lh secretion in the ewe: evidence for a regulation of tyrosine hydroxylase activity. | several neurotransmitters are implicated in the photoperiodic regulation of prolactin and luteinising hormone (lh) secretion in the ewe. this work investigated whether catecholamines, gamma-amino butyric acid (gaba), excitatory amino acids and serotonin diencephalic contents are affected by photoperiod and how such changes relate to the seasonal effects of photoperiod on lh and prolactin secretions. moreover, to determine whether photoperiod can influence catecholamine biosynthesis, the activity ... | 1996 | 8809677 |
| ventromedial preoptic prostaglandin e2 activates fever-producing autonomic pathways. | fever is thought to be initiated by pyrogenic cytokines inducing the production of prostaglandin e2 (pge2) in the preoptic area (poa); pge2 may act as a paracrine mediator that stimulates the neural pathways that raise body temperature. this essential role for prostaglandins in fever first was proposed 25 years ago, but the specific preoptic cell groups at which pge2 acts and the pathways through which fever is produced remain poorly understood. to better define the role of preoptic pge2 in feve ... | 1996 | 8815905 |
| neuropeptide y perfused in the preoptic area of rats shifts extracellular efflux of dopamine, norepinephrine, and serotonin during hypothermia and feeding. | this study examined the localized action of neuropeptide y (npy) on monoamine transmitter activity in the hypothalamus of the unrestrained rat as this peptide induced hypothermia, spontaneous feeding or both responses simultaneously. a guide tube was implanted in the anterior hypothalamic pre-optic area (ah/poa) of sprague-dawley rats. then either control csf vehicle or npy in a dose of either 100 ng/microliter or 250 ng/microliter was perfused by push-pull cannulae in this structure in the full ... | 1996 | 8829134 |
| blockade of lipopolysaccharide-induced fever by subdiaphragmatic vagotomy in guinea pigs. | it is generally believed that fever is mediated by certain cytokines produced by immune cells activated by exogenous pyrogens, e.g., lipopolysaccharides (lps), released into the circulation and transported to the brain there, the cytokines are thought to stimulate prostaglandin (pg) e2 production within the organum vasculosum laminae terminalis region. pge2 then may act as a febrigenic mediator locally or in the surrounding preoptic area (poa). however, whereas the increases in preoptic pge2 and ... | 1996 | 8836556 |
| effects of prenatal morphine and adult estrogen administration on mu-opioid inhibition of norepinephrine release from hypothalamic slices. | the present study tested the hypotheses that exposure to morphine in utero (10 mg/kg twice a day on gestation days 11-18) and acute estrogen treatment in adulthood alter mu-opioid regulation of hypothalamic norepinephrine (ne) release in sexually mature rats. both basal and kcl-stimulated ne releases were measured in superfused hypothalamic and preoptic area (poa) slices preloaded with 3h-ne. the mu-opioid receptor agonist d-ala2, mephe4-gly-ol5-enkephalin (damgo; 10 or 100 nm) or the opioid ant ... | 1996 | 8839356 |
| in vivo evidence for progesterone dependent decreases in serotonin release in the hypothalamus and midbrain central grey: relation to the induction of lordosis. | the effects of progesterone (p) on serotonin (5ht) overflow in the ventromedial hypothalamus (vmh), preoptic area (poa) and midbrain central grey (mcg) were studied using in vivo microdialysis. ovariectomized rats, pretreated with 5 micrograms estradiol, were anesthetized with chloral hydrate and stereotaxically implanted with dialysis probes directed towards one of the respective brain sites. extracellular 5ht levels stabilized 3 to 5 h following probe implantation. under stable baseline condit ... | 1996 | 8680878 |
| multiple b- and t-cell epitopes on a major allergen of kentucky bluegrass pollen. | the b- and t-cell epitopes of a recombinant grass allergen, rkbg60, were delineated using a set of overlapping synthetic peptides. direct binding by enzyme-linked immunosorbent assay (elisa) utilizing serum pools led to the identification of 13 murine immunoglobulin-, and nine to 13 human igg- and five to seven human ige-reactive overlapping peptides. of the peptides which bound to human ige antibodies, all but three peptides bound to human and/or murine igg antibodies. furthermore, eight out of ... | 1996 | 8698392 |
| forage systems for beef production from conception to slaughter: iii. finishing systems. | fall-weaned angus calves grazed or were fed different forages during winter followed by 1) n-fertilized tall fescue (festuca arundinacea schreb.) grazed alone, 2) bluegrass (poa pratensis l.)-white clover (trifolium repens l.) sequence grazed with tall fescue-red clover (trifolium pratense l.), or 3) bluegrass-white clover sequence grazed with alfalfa (medicago sativa l.)-orchardgrass (dactylis glomerata l.). heifers were supplemented with grain at 1% of bw from april until slaughter in july. on ... | 1996 | 8707721 |
| macrophage inflammatory protein-1beta (mip-1beta) produced endogenously in brain during e. coli fever in rats. | macrophage inflammatory protein-1 (mip-1) evokes an intense fever, independent of a prostaglandin mechanism, and is now thought to play an important role in the defence response to bacterial pyrogens. the purpose of this study was 2-fold: (i) to determine whether the potent doublet of this cytokine, mip-1beta, is actually produced in the brain in response to a pyrogenic dose of a lipopolysaccharide of escherichia coli and (ii) to determine the anatomical site of synthesis of this cytokine in the ... | 1996 | 8714712 |
| effect of fasting and immobilization stress on estrogen receptor immunoreactivity in the brain in ovariectomized female rats. | the present study examined the effect of 48-h fasting and 1-h immobilization on estrogen receptor immunoreactivity in selected hypothalamic areas and the nucleus of the solitary tract (nts) in ovariectomized rats. fasting induced an increase in er-immunoreactive cells in the paraventricular nucleus (pvn), periventricular nucleus (pevn) and nts compared with the unfasted control group. similarly, immobilization caused an increase in er-positive cells in the same areas, pvn, pevn and nts, versus t ... | 1996 | 8738253 |
| estrogenic control of preoptic area development in a carnivore, the ferret. | 1. evidence is reviewed which shows that a sexually dimorphic nucleus located in the dorsomedial portion of the male ferret's preoptic area/anterior hypothalamus (poa/ah), called the male nucleus of the poa/ah (mn-poa/ah), develops during fetal life in response to the action of estradiol, which is formed directly in the nervous system from circulating testosterone over the final quarter of a 41-day gestation. 2. results are summarized which establish that neurons which make up the mn-poa/ah are ... | 1996 | 8743964 |
| interaction between norepinephrine and prostaglandin e2 in the preoptic area of guinea pigs. | the release of norepinephrine (ne) and prostaglandin e2 (pge2) in the preoptic-anterior hypothalamus (poa) by systemically administered pyrogens suggests that both substances may mediate the febrile response. to investigate their possible interaction, we measured directly the levels of pge2 in the extracellular fluid of the poa of conscious guinea pigs microdialyzed intrapreoptically with exogenous ne over the entire course of their febrile response to endotoxin. acidified and buffered ne (nea, ... | 1996 | 8853372 |
| exogenous estrogen acts differently on production of estrogen receptor in the preoptic area and the mediobasal hypothalamic nuclei in the newborn rat. | expression of the estrogen receptor (er) in the preoptic area (poa) and the mediobasal hypothalamus (mbh) in newborn female rats was studied by immunohistochemistry (ihc) and in situ hybridization histochemistry (ishh). the number of er immunoreactive (er-ir) cells decreased and expression of er mrna was suppressed in the arcuate (arh) and the ventromedial (vmh) hypothalamic nuclei by daily injections of estradiol benzoate (eb) for ten consecutive days. in contrast, in the poa, expression of er ... | 1996 | 8856721 |
| evidence that brain nitric oxide synthase is the major nitric oxide synthase isoform in the hypothalamus of the adult female rat and that nitric oxide potently regulates hypothalamic cgmp levels. | recent studies suggest that nitric oxide (no) may function as a neurotransmitter in the hypothalamus. in order to provide further evidence supporting this contention, we examined: (1) whether the hypothalamus displays significant no synthase (nos) activity and whether the activity is inhibited by an nos inhibitor, (2) whether the different nos isoforms [brain (b)-nos, endothelial (e)-nos and macrophage (m)-nos] are expressed in the various nuclei of the hypothalamus of the random cycling adult f ... | 1996 | 8857603 |
| host genetic and adjuvant factors influence epitope specificity to a major recombinant grass allergen. | the role of host genetic and adjuvant factors in the induction of immune responses to a major recombinant kentucky bluegrass allergen was examined utilizing five strains of mice and two different adjuvants. analysis of the recombinant allergen-specific antibodies induced in these strains indicated that the antibodies of various isotypes were differentially regulated. in terms of ige antibody response, bdf1 and dba/2 were characterized as high responder, whereas balb/c, cba/j and c57bl/6 were int ... | 1996 | 8859227 |
| effects of ovariectomy on gnrh neuronal morphology in rhesus monkey (macaca mulatta). | gonadotropin releasing hormone (gnrh) neurons are typically simple, fusiform cells; however, over the course of prepubertal development increasing numbers take on a 'spiny' appearance. following gonadectomy there is a decrease in the frequency of these spiny gnrh neurons. these observations which were made in the rat suggest that gnrh neurons are directly affected by the gonadal steroid milieu, though they do not themselves contain receptors for these steroidal hormones. in that there are import ... | 1996 | 8866247 |
| estrogen and apoptosis in the developing sexually dimorphic preoptic area in female rats. | effect of estrogen on apoptotic cell death was studied in the two sexually dimorphic neuronal groups in the developing rat preoptic area (poa): the anteroventral periventricular nucleus of the poa (avpvn-poa); and the sexually dimorphic nucleus of the poa (sdn-poa). a specific labelling of nuclear fragmentation was performed by terminal deoxynucleotydyl transferase(tdt)-mediated dutp-biotin nick end-labeling method (tunel method) to demonstrate apoptosis. in the avpvn-poa whose size is larger in ... | 1996 | 8866522 |
| analgesic effects of the neurosteroid 3 alpha-androstanediol. | the efficacy of 5 alpha-androstane-3 alpha,17 beta-diol (3 alpha-androstanediol; 3 alpha-diol) and 4-pregnen-3,20-dione (progesterone; p) in promoting analgesia was investigated. ovariectomized rats received daily injections of 3 alpha-diol (0.6, 3.0, 6.0 and 7.5 mg/kg) or vehicle and twice daily injections of estradiol-17 beta (e2: 1 microgram) for 2 days. progesterone (0.5, 1.0, 2.0 and 4.0 mg/kg) or its vehicle was given on the third day and nociceptive testing using the radiant heat tailflic ... | 1996 | 8869550 |
| increased galanin and neuropeptide-y immunoreactivity within the hypothalamus of ovariectomised ewes following a prolonged period of reduced body weight is associated with changes in plasma growth hormone but not gonadotropin levels. | manipulation of diet is known to affect the secretion of the gonadotropins and growth hormone (gh). the former are under the direct regulation of hypothalamic gonadotropin-releasing hormone (gnrh) and the latter is under the dual control of gh-releasing hormone (ghrh) and somatostatin (srih). at the level of the hypothalamus, both galanin (gal) and neuropeptide y (npy) are thought to regulate the secretion of the above releasing and inhibiting factors. both peptides are also potent orexigenic ag ... | 1996 | 8875437 |
| behavioral effects of 3 alpha-androstanediol. ii: hypothalamic and preoptic area actions via a gabaergic mechanism. | we investigated whether 5 alpha-androstane-3 alpha, 17 beta-diol (3 alpha-androstanediol; 3 alpha-diol), a neurosteroid whose effects are primarily inhibitory to sexual behavior, may act through interactions with gamma-aminobutyric acid (gaba) receptor complexes (gbrs) in the medial basal hypothalamus (mbh) and the preoptic area (poa). in experiment (exp.) 1, ovariectomized (ovx) rats were implanted with bilateral guide cannulae aimed above the mbh and were later treated with 17 beta-estradiol ( ... | 1996 | 8883823 |
| levels of serum steroids, aromatase activity, and estrogen receptors in preoptic area, hypothalamus, and amygdala of b6d2f1 male house mice that differ in the display of copulatory behavior after castration. | most male b6d2f1 hybrid house mice continue to copulate after castration (continuers), whereas others do not (noncontinuers). copulation in continuers appears estrogen dependent. serum testosterone (t), 17 beta-estradiol (e2), and dihydrotestosterone (dht), as well as aromatase activity (aa) and estrogen receptor (er) levels in preoptic area (poa), hypothalamus (hyp), and amygdala (am) were measured to determine if continuers and noncontinuers differ in estrogen physiology. in general, continuer ... | 1996 | 8889004 |
| oviposition preferences of culex pipiens and culex restuans for infusion-baited traps. | the number of egg rafts oviposited by culex pipiens and culex restuans in infusion-baited ovitraps varied with the type of infusion substrate, infusion age, method of infusion preparation, and calendar date. in one or more tests, more culex egg rafts were collected from water infused with kentucky bluegrass sod, mixed grass clippings, straw, or a commercial rabbit chow than from a water control. infusions prepared with oak leaves, maple leaves, and sod soil were ineffective as culex oviposition ... | 1996 | 8723254 |
| changes in the binding characteristics of the mu, delta and kappa subtypes of the opioid receptor in the hypothalamus of the normal cyclic ewe and in the ovariectomised ewe following treatment with ovarian steroids. | the mu, delta and kappa opioid receptor subtypes were measured across the oestrous cycle of the ewe and in ovariectomised (ovx) ewes treated with oestrogen and/or progesterone. we have used a subtype-specific opioid receptor binding assay, in which [3h]diprenorphine non-preferentially labelled each receptor subtype in the presence of blocking concentrations of site-specific opioid analogues. the density and affinity of each receptor subtype was measured in the preoptic area (poa) of the hypothal ... | 1996 | 8691110 |
| lack of maternal influence of lamb consumption of locoweed (oxytropis sericea). | locoweeds (oxytropis and astragalus spp.) are toxic plants found on many rangelands. preferences for locoweed are learned; livestock often initially reject the plant, but learn to eat locoweed after continued exposure. maternal influences are important in shaping diet selection in young animals. we studied the influence of ewe consumption of locoweed on lamb selection of the plant. twenty-four ewes were divided into three treatment groups (n = 8): 1) ewes conditioned to eat locoweed (oxytropis s ... | 1996 | 8690669 |
| progesterone and 3 alpha-androstanediol conjugated to bovine serum albumin affects estrous behavior when applied to the mbh and poa. | ovariectomized rats with cannula over the medial basal hypothalamus (mbh) received implants of 3 alpha-diol conjugated to bovine serum albumin (bsa; 3 alpha-diol:bsa), free 3 alpha-diol diluted with bsa (3 alpha-diol&bsa), progesterone (p) conjugated to bsa (p:bsa), free p diluted with bsa (p&bsa), or bsa alone. 3 alpha-diol:bsa or 3 alpha-diol&bsa facilitated receptivity within 90 min. other estradiol-treated rats received steroid implants in the preoptic area (poa); those receiving p:bsa or p& ... | 1996 | 8889005 |
| pharmacokinetics of extracellular melatonin in siberian hamster forebrain. | in vivo brain microdialysis was used to characterize the pharmacokinetics of subcutaneously injected melatonin in the anterior hypothalamic-preoptic area (ah-poa) of the male siberian hamster. animals with a microdialysis probe implanted in the ah-poa were treated with a subcutaneous melatonin injection at 0900 h (3 h after lights-on) or 2000 h (2 h prior to lights-off). treatment with 2.5 or 0.25 mg/kg dosages of melatonin in saline vehicle induced peak concentrations of melatonin in ah-poa mic ... | 1996 | 8891318 |
| the role of apoptosis in sexual differentiation of the rat sexually dimorphic nucleus of the preoptic area. | the sexually dimorphic nucleus of the preoptic area (sdn-poa) in the rat hypothalamus is larger in volume in males than in females due to a larger number of cells in the nucleus. although the sdn-poa, and its development, have been extensively studied, the actual mechanism of its sexual differentiation has not been established. the results of previous studies have not supported a role for gonadal steroids in the regulation of neurogenesis or the determination of the migratory pathway perinatally ... | 1996 | 8896803 |
| nitric oxide and drinking behaviour. | the role of brain l-arginine/nitric oxide biochemical pathway in the regulation of drinking behaviour was investigated. drinking was induced by water deprivation or by intracerebroventricularly (i.c.v.) injected angiotensin ii. l-arginine, the amino-acid precursor of nitric oxide, i.c.v. injected, caused a dose-dependent reduction of the intake of water induced both by water deprivation and i.c.v. angiotensin ii (p < 0.001). l-name, inhibitor of nitric oxide synthase, reverted l-arginine antidip ... | 1996 | 8899905 |
| downregulation of mu-opioid receptor mrna in the mediobasal hypothalamus of the female guinea pig following morphine treatment. | ribonuclease protection assays were performed on the basal hypothalamus (bh), the preoptic area (poa) and the thalamus (thal) from female guinea pigs that were ovariectomized and implanted with morphine (n = 8) or placebo (n = 8) pellets for 1 week. an antisense [32p]rutp labeled riboprobe, representing a 280 bp fragment of the guinea pig mu-opioid receptor gene (spanning putative tm ii through eight residues of tm iv), protected a single rna band of 280 bp. in contrast to the rat, the guinea pi ... | 1996 | 8904800 |
| effect of melatonin on the release of gonadotropin-releasing hormone and cyclic amp from the rat hypothalamus: an in vitro study. | using an in vitro static incubation system of adult male rat hypothalami, we have studied the effect of melatonin on the release of gonadotropin-releasing hormone (gnrh) and cyclic adenosine monophosphate (camp). mediobasal hypothalamus (mbh) and preoptic area (poa) were incubated separately in minimum essential medium (mem) for 6 h. the release of gnrh was measured by radioimmuno-assay in the incubation medium sampled every 7.5 min. in the mbh and poa incubation medium, the mean amount of gnrh ... | 1996 | 8910811 |
| neural systems mediating the negative feedback actions of estradiol and progesterone in the ewe. | the ewe shows a marked seasonal variation in the effects of ovarian steroids on pulsatile gnrh secretion. in the breeding season, progesterone inhibits gnrh pulse frequency, while estradiol suppresses pulse amplitude. in anestrus, both steroids inhibit pulse frequency. the effects of progesterone in both seasons are mediated by endogenous opioid peptides (eop) that act in the preoptic area (poa) and medial basal hypothalamus (mbh). however, knife cut studies indicate that actions in the mbh are ... | 1996 | 8917901 |
| laryngeal biomechanics of the singing voice. | by transnasal fiberoptic laryngoscopy, patients with functional voice often demonstrate abnormal laryngeal biomechanics, commonly supraglottic contraction. appropriately, such conditions are sometimes termed muscle tension dysphonias. singers working at the limits of their voice may also transiently demonstrate comparable tension patterns. however, the biomechanics of normal singing, particularly for different singing styles, have not been previously well characterized. we used transnasal fibero ... | 1996 | 8969758 |
| dislodgeability of chlorpyrifos and fluorescent tracer residues on turf: comparison of wipe and foliar wash sampling techniques. | residential use of pesticides has increased substantially in the united states over the past twenty years. contact with pesticide-treated turf may result in dermal exposures, particularly among children. this study evaluated wipe sampling and foliar wash techniques to measure chlorpyrifos on turf following insecticidal treatments with dursban 4e. residues of the fluorescent tracer uvitex ob were also measured as part of a larger study adapting video imaging analysis to children's exposure to pes ... | 1996 | 8975830 |
| characterization of dac g 4, a major basic allergen from dactylis glomerata pollen. | monoclonal antibodies were produced against dac g 4, a purified major basic allergen from dactylis glomerata pollen. their ability to be used for immunopurification of dac g 4 was studied on a biacore apparatus (pharmacia). the allergen was purified by affinity chromatography with one monoclonal antibody. its precise molecular mass, 59,185 +/- 30 d, was determined by mass spectrometry. its isoelectric point is 10.4. sodium dodecylsulfate-polyacrylamide gel electrophoresis and immunoblotting show ... | 1996 | 8977507 |
| susceptibilities of different test systems from maize (zea mays), poa annua, and festuca rubra to herbicides that inhibit the enzyme acetyl-coenzyme a carboxylase | the susceptibilities of maize (zea mays cv. champ) and two graminicide-resistant grass species, poa annua (annual meadow grass) and festuca rubra (red fescue), to two aryloxyphenoxypropionates (quizalofop and fluazifop) and a cyclohexanedione (sethoxydim) graminicide were evaluated in leaf blades and isolated chloroplasts, and by assaying acetyl-coenzyme a carboxylase (accase) in desalted leaf homogenates. the graminicide resistance of p. annua and f. rubra appeared to be at the level of accase. ... | 1996 | 8980037 |
| impact on salivary gland degeneration by putative ecdysteroid antagonists and agonists in the ixodid tick amblyomma hebraeum | ecdysteroids cause salivary gland degeneration in female ixodid ticks. we tested the effects of the following compounds on salivary gland degeneration in the ixodid tick amblyomma hebraeum koch: hhcs (22s,23s-homocastasterone), ssbr (22s,23s-homobrassinolide), stgm (2alpha,3alpha(oh)2-delta22-stigmasten-6-one), rh 5849, and rh 5992. the first three are brassinosteroids (putative ecdysone antagonists) and the last two are nonsteroidal mimics of ecdysone in a variety of insects. in vitro, hhcs (up ... | 1996 | 8980038 |
| cloning and expression pattern of hor v 9, the group 9 pollen isoallergen from barley. | in this study we report the cloning, sequence, and characterization of hor v 9 allergen cdnas from barley (hordeum vulgare) pollen. structural homologues of kentucky bluegrass (poa pratensis) group 9 pollen allergens were identified in a cdna library of barley pollen expressed mrnas. the hor v 9 cdna clone (hvp9742) contained an open reading frame encoding 313 amino acids which included a putative 27-residue signal peptide and one asparagine sequon for glycosylation. the mrna corresponding to cl ... | 1996 | 8982067 |
| effects of nitric oxide on stimulated release of norepinephrine from female rat hypothalamic slices. | norepinephrine (ne) is an important neurotransmitter involved in ovarian steroid hormone regulation of female reproductive function in rats. nitric oxide (no) has also been suggested to be an essential mediator of gonadotropin-releasing hormone release and of lordosis behavior of female rats. these studies used a superfusion system to investigate the hypothesis that no regulates [3h]ne release in the preoptic area (poa) and hypothalamus (hyp), brain regions that mediate ovarian steroid effects o ... | 1996 | 9001705 |
| inhibition of sexual behaviour and the luteinizing hormone surge by intracerebral progesterone implants in the female sheep. | in female sheep, progesterone blocks the induction by oestradiol of both sexual behaviour and the pre-ovulatory surges of gonadotrophin releasing hormone (gnrh) and luteinising hormone (lh). however, the central sites of action of progesterone remain poorly defined, so we attempted to locate them by implanting progesterone intracerebrally in ovariectomised ewes treated with exogenous steroids to induce oestrous behaviour and the lh surge. single bilateral implants or a double bilateral implants ... | 1996 | 9001713 |
| effects of androgen on brain and pituitary androgen receptors and lh secretion of male guinea pigs. | to study the tissue-specific control of androgen receptors by circulating androgens, guinea pigs were castrated or castrated and treated with crystalline testosterone propionate. levels of serum androgens and lh were measured and brain and peripheral tissues were collected for determination of androgen receptor levels under differing androgen states. we found that circulating androgen levels changed rapidly following castration or treatment with exogenous androgen. lh secretion was coupled to ci ... | 1996 | 9010323 |
| characterization of gonadotropin-releasing hormone gene transcripts in a mouse hypothalamic neuronal gt1 cell line. | we have characterized the nuclear and cytoplasmic rna transcripts derived from the gonadotropin releasing hormone (gnrh) gene in a mouse hypothalamic neuronal gt1 cell line. analyses of nuclear gnrh rna precursors present in the gt1 cells by rnase protection assay show that there is no particular order of intron excision, suggesting the existence of multiple processing pathways. a similar pattern is observed in mouse preoptic area-anterior hypothalamus (poa-ah). in gt1 cells, approximately 5% of ... | 1996 | 9013781 |
| avermectin b1, isazofos, and fenamiphos for control of hoplolaimus galeatus and tylenchorhynchus dubius infesting poa annua. | avermectin b, isazofos, and fenamiphos were evaluated in greenhouse experiments for efficacy against two common turfgrass parasites, hoplolaimus galeatus and tylenchorhynchus dubius. treatments in all experiments were arranged in a completely randomized design and replicated four times. in the first experiment, avermectin b at rates of 0.2 and 0.4 kg a.i./ha and isazofos at rates of 2.3 and 23 kg a.i./ha significantly reduced populations of both species of parasitic nematodes compared to control ... | 1996 | 19277196 |
| development of effective modified cellulase for cellulose hydrolysis process. | cellulase was modified with amphilic copolymers made of alpha-allyl-omega-methoxy polyoxyalkylene (poa) and maleic acid anhydride (maa) to improve the cellulose hydrolytic reactivity and cellulase separation. amino groups of the cellulase molecule are covalently coupled with the maa functional groups of the copolymer. at the maximum degree of modification (dm) of 55%, the modified cellulase activity retained more than 80% of the unmodified native cellulase activity. the modified cellulase shows ... | 1995 | 18623190 |
| characterization of aromatase cytochrome p-450 mrna in rat perinatal brain, ovary and a leydig tumor cell line: evidence for the existence of brain specific aromatase transcripts. | the conversion of androgens to estrogens is catalyzed by the aromatase cytochrome p-450 (p-450(arom)) in a veriety of tissues and cell types in vertebrates. the manner in which aromatase activity is regulated appears to be quite different, even between different tissues of a single species. in the current study, we have determined the sequence of the 5' end of the aromatase mrna in a rat leydig tumor cell line, r2c, and in three rat tissue [adult ovary, perinatal amygdala (amy), and medial basal ... | 1995 | 21153233 |
| effects of the unilateral implant of haloperidol at the preoptic-anterior hypothalamic area, on ovulation. | in order to analyse whether the participation of the dopaminergic system of the preoptic-anterior hypothalamic area (poa-aha) in the regulation of ovulation is asymmetric and varies during the estrous cycle of the rat, as it occurs with the cholinergic system, the effects of a unilateral implant of haloperidol were studied. cyclic fourth-day rats with a permanent cannula directed to the right or left side of the poa-aha, at 13:00 h of estrous (e), diestrous 1 or 2 (d1, d2) or proestrus (p), rece ... | 1995 | 21153240 |
| sex-specific changes in preoptic regulatory factor-1 and preoptic regulatory factor-2 mrna expression in the rat brain during development. | preoptic regulatory factor-1 (porf-1) and preoptic regulatory factor-2 (porf-2) are two novel peptide genes which are expressed in the central nervous system. expression is modified by age and by hormones of the reproductive system. in this study nuclease protection assays were employed to investigate porf-1 and porf-2 mrna expression in the cerebral cortex (cc), hippocampus (hipp), preoptic area (poa) and medial basal hypothalamus (mbh) of male and female rats, aged 15, 30 and 60 days. porf-1 a ... | 1995 | 21153245 |
| pre- and post-translational regulation of aromatase by steroidal and non-steroidal aromatase inhibitors. | treatment of castrated quail with testosterone (t) reliably activates male copulatory behavior and, at the same time, increases the aromatase activity (aa), the number of aromatase-immunoreactive (aro-ir) cells and the concentration of aromatase mrna as measured by rt-pcr in the brain. all these effects can be mimicked by estrogens. the behavioral effects of t can be blocked by a variety of aromatase inhibitors and, in parallel, the aa is strongly inhibited in the preoptic area (poa). we showed ... | 1995 | 8925290 |
| the role of neuropeptide y (npy) in the control of lh secretion in the ewe with respect to season, npy receptor subtype and the site of action in the hypothalamus. | neuropeptide y1-36 (npy1-36) acts through y1 and y2 receptors while the c-terminal npy fragments npy18-36 and n-acetyl[leu28,31]pnpy24-36 act only through the y2 receptor. we have investigated the effects of intracerebroventricular (i.c.v.) administration of npy1-36, npy18-36 and n-acetyl[leu28,31]pnpy24-36 on lh secretion in the ovariectomised (ovx) ewe. these peptides were administered into a lateral ventricle (lv) or the third ventricle (3v) of ovx ewes during the non-breeding and breeding se ... | 1995 | 8543927 |
| effects of pinealectomy and melatonin treatments on serotonin uptake and release from synaptosomes of rat hypothalamic regions. | this study examined the effects induced by long-term pinealectomy, daily melatonin treatment to pinealectomized and intact rats, and a single melatonin injection on [14c]-serotonin (5-ht) uptake and release from synaptosomes obtained of hypothalamic regions. pinealectomy inhibited the accumulation of labeled 5-ht by synaptosomes of the preoptic area-anterior hypothalamus (poa-ah), but it failed to alter the [k+]-evoked 5-ht release. melatonin treatment for 10 consecutive days to pinealectomized ... | 1995 | 8746796 |
| progesterone suppression of glutamic acid decarboxylase (gad67) mrna levels in the preoptic area: correlation to the luteinizing hormone surge. | the progesterone-induced lh surge in the estrogen-primed rat is thought to be mediated through interneurons since lhrh neurons reportedly lack steroid receptors. along these lines, glutamate and gamma-aminobutyric acid (gaba) neurons are considered to be two of the major interneurons in the hypothalamus involved in the control of lhrh and lh secretion. glutamate is a major excitatory amino acid neurotransmitter while gaba is a major inhibitory amino acid neurotransmitter in the control of lh sec ... | 1995 | 8751281 |
| a revised critical period for the sexual differentiation of the sexually dimorphic nucleus of the preoptic area in the rat. | the volume of the sexually dimorphic nucleus of the preoptic area (sdn-poa) of the rat is several times larger in males than in females. several studies have established the importance of gonadal steroids perinatally in the sexual differentiation of the sdn-poa as well as a critical period for the permanent influences of exogenous androgen on the volume of the nucleus. recent preliminary evidence from this laboratory had suggested, however, that the critical period for the effects of the removal ... | 1995 | 8751283 |
| lipopolysaccharide-induced fos expression in hypothalamic nuclei of neonatal rats. | the inability of neonates to fully evoke the acute-phase reaction to infection is thought to be due in part to central nervous system immaturity. we used the expression of fos protein to evaluate whether acute-phase reaction deficits in neonates may indeed be linked to unresponsiveness of brain regions that mediate the responses to infection in adult animals. in this study, we used lipopolysaccharide (lps) as the infectious agent. rats aged 0-1, 3, 6, 9, 12 and 15 days were divided into groups t ... | 1995 | 8739201 |
| projections from visual areas of the cerebral cortex to pretectal nuclear complex, terminal accessory optic nuclei, and superior colliculus in macaque monkey. | the purpose of this study was to analyze the projections from visually related areas of the cerebral cortex of rhesus monkey to subcortical nuclei involved in eye-movement control; i.e., the pretectal nuclear complex, the terminal nuclei of the accessory optic system (aos), and the superior colliculus (sc). the anterograde tracer 3h-leucine was pressure injected bilaterally into the cortex of six monkeys (for a total of 12 cases) involving the primary visual cortex (area 17); the medial prestria ... | 1995 | 8847410 |
| oligodendrocyte development in plp "pt" mutant rabbits: glycolipid antigens and plp gene expression. | paralytic tremor (pt), a hereditary neurological disorder of rabbits is a recessive, x-linked point mutation of the gene for proteolipid protein (plp) biosynthesis. this mutation results in substitution of histidine by glutamine in the plp molecule and produces severe hypomyelination. in the present study, we investigated the developmental expression of myelin-oligodendrocyte-specific glycolipid markers by means of elisa assay. while immunoreactivity with antibodies recognising proligodendroblas ... | 1995 | 8847995 |
| the inhibitory effect of beta-endorphin on lh release in ovariectomized rats does not involve the preoptic gabaergic system. | in rats, beta-endorphin (beta-end) and gamma-aminobutyric acid (gaba) suppress lh secretion by hypothalamic mechanisms involving the preoptic area (poa). systemic injection of naloxone (nal) increases lh secretion in male rats, an effect which can be prevented by coadministration of gaba agonists. application of nal into the poa of ovariectomized (ovx), progesterone substituted sheep modulates preoptic gaba release. these findings have been interpreted such that the endogenous opioids act via th ... | 1995 | 8536061 |
| some properties of the ecdysteroid receptor in the salivary gland of the ixodid tick, amblyomma hebraeum. | salivary gland degeneration in ixodid ticks is triggered by an ecdysteroid hormone. we used [3h]ponasterone a (poa) as a specific ligand to detect the ecdysteroid receptor in the salivary glands of large, partially fed female ticks (amblyomma hebraeum koch; acari: ixodidae). binding of [3h]poa was thermolabile and sensitive to pronase, but not to dnase or rnase, indicating that the ligand binds to a protein. scatchard analysis of [3h]poa binding strongly suggested the presence of an ecdysteroid ... | 1995 | 8536946 |
| t-cell epitopes of phl p 1, major pollen allergen of timothy grass (phleum pratense): evidence for crossreacting and non-crossreacting t-cell epitopes within grass group i allergens. | the use of peptides representing t-cell epitopes of allergens is a modern concept for improvement of specific immunotherapy. a prerequisite for this approach is the identification of t-cell epitopes of atopic allergens. | 1995 | 8543758 |
| ovariectomy and age alter gonadotropin hormone releasing hormone-noradrenergic interactions. | the noradrenergic (na) system influences gonadotropin hormone releasing hormone (gnrh) neurons resulting in the luteinizing hormone surge. direct neuroanatomical interactions between preoptic area (poa) gnrh neuronal elements and na [i.e., dopamine-beta-hydroxylase (dbh)] terminals; effects of short-term ovariectomy (s-ovx) on these interactions; and the stability of these interactions with age were studied in young (5-month-old) proestrous, 5-month-old s-ovx (6d), old (24-month-old) constant di ... | 1995 | 8544912 |
| comparison of ige and igg antibody responses of atopic individuals with sensitization to tree and grass pollens. | sera of atopic individuals with predominant sensitization to either tree pollen (tas) or tree and grass pollens (tgas) as well as of nonatopic subjects (nas) were analyzed for ige, igg, and igg4 antibodies specific for grass pollens allergens. of 600 atopic individuals with serum ige antibodies specific for birch pollen allergens, 54% also had serum ige antibodies specific for grass pollen. the mean titers of igg antibodies specific for grass pollen proteins were about 10 times higher in the ser ... | 1995 | 8546268 |
| dissociation of the restoration of copulatory behavior and the testicular morphology in old male rats with fetal brain grafting. | improvement of copulatory activity has been reported in aged male rats bearing the fetal preoptic area (poa), however, whether the fetal poa graft has any effect on the gonad of aged male rats has not been established. in the present study, the testicular histology and the sexual behavior were studied in 20 old (18-19 months) long-evans male rats after fetal brain transplantation. animals were divided into three groups: (1) poa-grafted group (n = 6): fetal poa neurons were grafted into the poa, ... | 1995 | 8549230 |
| preoptic rather than mediobasal hypothalamic amino acid neurotransmitter release regulates gnrh secretion during the estrogen-induced lh surge in the ovariectomized rat. | inhibitory and excitatory amino acid neurotransmitters have been suggested to participate in the feedback actions of estradiol (e2) on lh secretion. in the rat estrogen-receptive neurons have been demonstrated in the preoptic/anterior hypothalamic area (poa) and mediobasal hypothalamus/median eminence (mbh) and many of these neurons utilize gamma-aminobutyric acid (gaba) as neurotransmitter. the actions of excitatory amino acids (eaa) differ in ovariectomized (ovx) and ovx e2-substituted rats in ... | 1995 | 8559279 |
| cloning, sequencing and expression in escherichia coli of pha a 1 and four isoforms of pha a 5, the major allergens of canary grass pollen. | the pollen of canary grass, which was introduced as a pasture grass from europe, is a major allergen source in the external environment of southern australia. this study was performed to characterize the major recombinant allergens of canary grass pollen. it is anticipated that recombinant allergens may be useful in diagnosis and immunotherapy of grass pollen induced allergies. | 1995 | 8564724 |
| facilitation of the arterial baroreflex by the preoptic area in anaesthetized rats. | 1. activation of cell bodies in the ventrolateral part of the midbrain periaqueductal grey matter (pag) facilitates the arterial baroreflex via the nucleus raphe magnus. the facilitatory effects of stimulation within the hypothalamus on the arterial baroreflex and their relation to the pag and nucleus raphe magnus were studied in urethane- and chloralose-anaesthetized rats. 2. systematic mapping experiments revealed that the preoptic area (poa) is the principal location in the hypothalamus of ne ... | 1995 | 8568691 |
| tianeptine treatment induces regionally specific changes in monoamines. | tianeptine is an atypical tricyclic antidepressant that facilitates serotonin (5-ht) reuptake. tianeptine (10 mg/kg) or saline was administered intraperitoneally to male rats daily for 4 days. monoamine levels were measured in micropunches of discrete brain nuclei that are implicated in mood and cognition. in addition, the rates of 5-ht and norepinephrine (ne) accumulation were determined by the pargyline method. few changes were noted in the 5-ht system. 5-ht levels were increased by short-term ... | 1995 | 8574656 |
| fever induced in rats by intrahypothalamic macrophage inflammatory protein (mip)-1 beta: role of protein synthesis. | the effect of macrophage inflammatory protein-1 beta (mip-1 beta) on body temperature, following its injection into the anterior hypothalamic pre-optic area (ah/poa), was examined by a radiotelemetry system in the freely moving rat. the purpose of this study was to examine the action of an inhibitor of protein synthesis, anisomycin, on the pyrexia which follows intrahypothalamic injection of mip-1 beta. the micro-injection of 10 to 20 pg mip-1 beta into the ah/poa induced a dose-dependent monoph ... | 1995 | 8583502 |
| effect of hypothalamic infusion of a dopamine d1 receptor antagonist on prolactin secretion in the ewe. | in this study we investigated whether dopamine d1 receptors in the hypothalamus are involved in the control of prolactin secretion in ovariectomised, oestradiol implanted ewes. the d1 antagonist sch23390 or vehicle was infused into either the preoptic area (poa) or the ventromedial hypothalamus (vmh). during infusion into the vmh, prolactin concentrations declined significantly and did not return to control values until more than 60 min after the infusions had stopped. in contrast, infusion into ... | 1995 | 8593594 |
| effects of hypothalamic lesions on the body temperature rhythm of the golden hamster. | the effects of electrolytic and neurotoxic lesions of the suprachiasmatic nucleus (scn) and preoptic area (poa) of the anterior hypothalamus were studied by temperature telemetry in the golden hamster (mesocricetus auratus) examined under two ambient temperature conditions: 24 degrees c and 6 degrees c. although attempted lesions with microinjections of ibotenic acid proved unsuccessful, electrolytic lesions of the scn eliminated the circadian rhythm of body temperature (crt), indicating an acti ... | 1995 | 8595199 |
| effect of gabaergic compounds on gonadotropin-releasing hormone receptor gene expression in the rat. | using a competitive reverse transcription-polymerase chain reaction (rt-pcr), the amounts of gnrh receptor (gnrhr) transcript in a discrete nucleus micropunched from rat brain slices were determined. gnrhr transcript was highly expressed in anterior pituitary >> median eminence > posterior mediobasal hypothalamus (pmbh) > preoptic area (poa) but not in cortex and posterior pituitary, which were used as control tissues. to examine the effect of gaba on gnrhr transcript level, 10 nmol of muscimol, ... | 1995 | 7750481 |
| neuromodulation of transplanted gonadotropin-releasing hormone neurons in male and female hypogonadal mice with preoptic area brain grafts. | implantation of normal preoptic area (poa) tissue into the third ventricle of adult hypogonadal (hpg) mice provides a source of gnrh neurons that innervate the host median eminence and stimulate reproductive development in the sterile mutants. to further evaluate graft-host integration, the effects of n-methyl-d,l-aspartic acid (nma) and opiate antagonists on lh secretion in hpg mice with poa transplants (hpg/poa) were tested. nma challenges significantly stimulated lh secretion in 10 of 11 hpg/ ... | 1995 | 7756451 |
| opioid precursor gene expression in the human hypothalamus. | using in situ hybridization histochemistry, we studied the distribution of neurons that express preproopiomelanocortin (pre-pomc), preprodynorphin (pre-pdyn), and preproenkephalin (pre-penk) gene transcripts within the human hypothalamus and surrounding structures. of the three opioid systems, pre-pomc neurons have the most restricted distribution. pre-pomc cells are most numerous in the infundibular nucleus and retrochiasmatic area of the mediobasal hypothalamus; a few labeled cells are present ... | 1995 | 7759618 |
| hypothalamic processing of beta-endorphin in female c57bl/6j mice is altered at middle age. | beta-endorphin (beta-endo) (1-31) is the active opioid peptide product of pro-opiomelanocortin processing. further post-translational modifications of beta-endo(1-31) yield beta-endo(1-27), (1-26) and their acetylated forms which are considered to be opiate receptor antagonists. mechanistically, alteration in opiatergic properties is likely to result in the loss of a number of physiological functions including reproductive capacity. the purpose of this study was to determine whether there are ch ... | 1995 | 7738464 |
| estrogen receptor mrna levels in the preoptic area of neonatal rats are responsive to hormone manipulation. | testosterone, after conversion to estrogen, masculinizes the developing preoptic area (poa) of rats, via binding to intracellular estrogen receptors located within the poa. our previous studies have shown what seems to be a paradox, in that the levels of estrogen receptor mrna are lower in males than in females. in the present study, we examined the effects of hormone manipulations on estrogen receptor (er) mrna levels in the preoptic area of neonatal male and female rats to test the hypothesis ... | 1995 | 7743645 |
| adrenalectomy alters the response of neurons in the bed nucleus of the stria terminalis to electrical stimulation of the medial amygdala. | this study was performed to characterize the effects of adrenalectomy (adx) on electrical activity and synaptic responses of bed nucleus of the stria terminalis (bnst) and preoptic area (poa) neurons, which are involved in the control of limbic-hypothalamo-pituitary-adrenocortical (lhpa) activity. adrenalectomy altered the response of bnst neurons to medial amygdala (ame) stimulation, increasing the proportion of excitatory responses and reducing the number of cells inhibited. no such effects we ... | 1995 | 7882051 |
| the effect of prenatal exposure to the phytoestrogen genistein on sexual differentiation in rats. | exposure to naturally occurring estrogens during critical periods of development can alter morphologic and physiologic markers of sexual differentiation. the current experiment characterizes the effects of in utero treatment with genistein, an isoflavonoid phytoestrogen, on birth weight, anogenital distance (agd) at birth. gnrh stimulated luteinizing hormone (lh) secretion, volume of the sexually dimorphic nucleus in the preoptic area of the hypothalamus (sdn-poa), puberty onset, and vaginal cyc ... | 1995 | 7892297 |
| the effect of neonatal exposure to diethylstilbestrol, coumestrol, and beta-sitosterol on pituitary responsiveness and sexually dimorphic nucleus volume in the castrated adult rat. | the neonatal hormone environment influences the sexually differentiated patterns of development. estrogens, derived from intracerebral aromatization, promote male pattern development of the central nervous system. the purpose of this study was to determine the effects of neonatal exposure to environmental estrogens on luteinizing hormone (lh) secretion and development of the sexually dimorphic nucleus of the medial preoptic area (sdn-poa) in castrated adult rats. neonatal rats of both sexes rece ... | 1995 | 7892299 |
| mapping of hypothalamic sites involved in the effects of npy on body temperature and food intake. | the objective of the present study was to identify hypothalamic sites that might be implicated in the effects of neuropeptide y (npy) on both body temperature and food intake. for this purpose, the effects of direct microinjections of npy in several doses (0.156-20 micrograms) into discrete hypothalamic nuclei on body temperature were examined in rats. to examine specificity of effects, food consumption of animals following injections was also measured. results indicate that the influence of npy ... | 1995 | 7895089 |
| effects of npy and npy2-36 on body temperature and food intake following administration into hypothalamic nuclei. | our previous in vivo structure-activity studies suggested that the putative receptors mediating the effects of npy and npy2-36 on food intake and body temperature are pharmacologically different [17]. in the present study, we examined and compared dose-related effects of npy and npy2-36 on ad lib food intake and rectal temperature after administration into discrete hypothalamic nuclei of the rat. results indicate that npy and npy2-36 have opposite effects on body temperature to those of npy when ... | 1995 | 7895090 |
| cytokines and thermoregulation: interleukin-9 injected in preoptic area fails to evoke fever in rats. | a number of the members of the family of cytokines including il-1, il-2, il-6, and il-11 act directly in the brain to induce a febrile response in the rat and other species. the purpose of this study was to examine the effect of interleukin-9 (il-9) when this cytokine is applied directly to the thermosensitive and pyrogen reactive region of the anterior hypothalamic, preoptic area (ah/poa). in male sprague-dawley rats, guide cannulae for microinjection into the ah/poa were implanted stereotaxica ... | 1995 | 7895096 |
| sex dimorphic alterations in postnatal brain catecholamines after gestational morphine. | the concentration of brain catecholamines was measured in the hypothalamus, preoptic area (poa), frontal cortex, cerebellum, and striatum of rats exposed in utero to morphine (5-10 mg/kg/twice daily) during gestation days 11-18. prenatal morphine induced regionally specific, sexually dimorphic alterations in male and female norepinephrine (ne), and dopamine (da) content at different postnatal ages. prenatal morphine significantly increased ne content in the hypothalamus of both sexes at postnata ... | 1995 | 7895097 |
| glutamate: a major excitatory transmitter in neuroendocrine regulation. | excitatory amino acids (eaas), such as glutamate and aspartate, are found in large concentrations in presynaptic boutons of a variety of important hypothalamic nuclei, including the arcuate nucleus, supraoptic nucleus, suprachiasmatic nucleus, paraventricular nucleus, organum vasculosa of the lamina terminalis (ovlt) and preoptic area (poa). likewise, the different ionotropic/metabotropic eaa receptor subtypes are found in the same regions of the hypothalamus although there are differences in th ... | 1995 | 7898626 |
| is the inhibitory action of estradiol on luteinizing hormone pulse frequency in anestrous ewes mediated by noradrenergic neurons in the preoptic area? | this study tested the hypothesis that estradiol inhibits luteinizing hormone (lh) pulse frequency in anestrous ewes by increasing the activity of an inhibitory noradrenergic (ne) system that acts in the ovine preoptic area (poa). the effects of estradiol on the release of ne and other neurotransmitters in the poa were determined using intracranial microdialysis. microdialysis probes (5 mm membrane length) were inserted via chronic guide tubes into the poa. ringer's solution was pumped through th ... | 1995 | 7898633 |
| regulation of gaba transporter activity and mrna expression by estrogen in rat preoptic area. | this study has examined whether estrogen regulates gaba transporter synthesis and activity in the female rat brain. in the first experiment in situ hybridization studies examined the effects of ovariectomy on cellular gaba transporter-1 (gat-1) mrna content. a 25% decrease in gat-1 mrna expression was detected within the medial preoptic area (mpoa) but not the parietal cortex, magnocellular preoptic nucleus (mg-poa) or caudate-putamen (c-p). estrogen replacement for 7 d returned gat-1 mrna conte ... | 1995 | 8613763 |
| cdc recommendations for civilian communities near chemical weapons depots: guidelines for medical preparedness--cdc. publication of final recommendations. | on july 27, 1994, cdc published in the federal register, 59 fr 38191, "cdc recommendations for civilian communities near chemical weapons depots: guidelines for medical preparedness" and requested public comment. seven people sent comments; many were responding on behalf of governments or other institutions in affected communities. these comments are available upon request. these recommendations incorporate changes made in response to the comments received and constitutes cdc's final recommendat ... | 1995 | 10143398 |
| cairo and the changing definition of population and development issues. | this article discusses a few intellectual and ideological developments during the 1980s and 1990s which impacted on the goals articulated at the un international conference on population and development and in its plan of action (poa). a major shift occurred between the bucharest plan of 1974 and the 1994 poa. the economic view was improved by an emphasis on the ecological, human rights, and nongovernmental organization (ngo) participatory views. the bucharest plan promoted the institutionali ... | 1995 | 12294863 |