Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| [host factors in cancer chemotherapy]. | cancer grows in interaction with the host, that is, a host-tumor relationship exists. investigations of host factors in patients receiving cancer chemotherapy are important, as they reveal the conditions in which a tumor response can develop. furthermore, reliable host factors, if present, will be useful for quantitative evaluation of the effects of treatment. we have investigated the following three categories of host factors in relation to the effects of cancer chemotherapy and/or immunotherap ... | 1986 | 3729433 |
| posterior parietal projections to the intraparietal sulcus of the rhesus monkey. | a cyto- and myeloarchitectonic parcellation of the intraparietal sulcus in the rhesus monkey was correlated with the pattern of afferent connections from the parietal lobe as determined by autoradiographic techniques. area pea in the upper bank receives topographically-organized input from the ventral and caudal superior parietal lobule and the medial surface of the parietal lobe. area poa in the lower bank is the recipient of a projection from the rostral inferior parietal lobule. area ipd, sit ... | 1986 | 3720878 |
| decrease of locomotor activity by injections of carbachol into the anterior hypothalamic/preoptic area of the rat. | cholinergic elements in forebrain structures are implicated in locomotion but their role is still unclear. in the present study, the effects of intracerebrally injected carbachol or atropine on spontaneous locomotion and rearing activity were investigated. effective injection sites were found in the area between frontal planes 5.3 and 6.3 mm from interaural plane and between the ventricle wall and lateral plane 1.1 mm from the midline which corresponds to the medial anterior hypothalamic/preopti ... | 1986 | 3719372 |
| preoptic lesions increase the display of lordosis by male rats. | male rats do not normally show feminine patterns of sexual behavior even when injected with the ovarian hormones estrogen and progesterone. we find that brain lesions which damage the preoptic-anterior hypothalamic continuum augment the display of lordosis in hormone-treated male rats. the most effectively feminizing brain lesions are ones which bilaterally destroy a substantial portion of the medial preoptic area encompassing the sexually dimorphic nucleus of the preoptic area (sdn-poa). males ... | 1986 | 3708321 |
| formation of behaviorally effective 17 beta-estradiol in the dove brain: steroid control of preoptic aromatase. | the preoptic area (poa) of the male dove is a known target area for separable behavioral actions of testosterone and 17 beta-estradiol (e2) and contains an active aromatase system. we have examined the regulatory influence of gonadal hormones on aromatase using an in vitro microassay that measures conversion of [1 alpha, 2 alpha-3h]testosterone to e2 in anatomically defined brain samples of individual animals. preoptic aromatase activity, which is higher in males than females, is decreased (77%) ... | 1986 | 3698910 |
| studies of instrumental behavior with sexual reinforcement in male rats (rattus norvegicus): ii. effects of preoptic area lesions, castration, and testosterone. | we studied effects of lesions to the medial preoptic area (poa), castration, and testosterone replacement on instrumental and unconditioned sexual behavior in male rats. we achieved instrumental measures of sexual motivation by training males to work for an estrous female, presented in an operant chamber under a second-order schedule of reinforcement. poa lesions abolished mounts, intromissions, and ejaculation but did not disrupt instrumental responses, investigation of the female, or abortive ... | 1987 | 3691063 |
| cortisol alters firing rate and synaptic responses of limbic forebrain units. | single units antidromically identified as projecting to the hypothalamic paraventricular nucleus (pvn) from the lateral septum (ls) and preoptic area (poa) were recorded in adrenalectomized male rats. eight of the 15 poa units identified as projecting to the pvn were affected by reciprocally projecting pathways also showing either orthodromic excitation or inhibition. a variety of responses from poa units following cortisol injection suggested a heterogeneity of pvn afferent projections arising ... | 1987 | 3690363 |
| plasma lh rises rapidly following mating in hypogonadal female mice with preoptic area (poa) brain grafts. | hypogonadal female mice, genetically deficient in gonadotropin releasing hormone (gnrh), respond to preoptic area (poa) grafts obtained from normal fetal or neonatal mice with increased gonadotropin levels, ovarian and uterine development and continual vaginal estrus rather than spontaneous ovulatory cyclicity. previous studies showed that such mice became pregnant following one overnight pairing with a normal male, indicating reflex ovulation. the present study evaluated plasma lh concentration ... | 1987 | 3690294 |
| increased norepinephrine turnover in the median preoptic nucleus following reduced extracellular fluid volume. | the role of noradrenergic input to fluid balance regulatory systems in the anterior hypothalamus was studied by examination of norepinephrine (ne) turnover during reduction of systemic extracellular fluid volume. extracellular fluid volume was decreased iso-osmotically by subcutaneous polyethylene glycol (peg), known to increase thirst and vasopressin secretion. ne turnover was assessed by measuring the decline of ne concentration in brain micropunches after administration of alpha-methyl tyrosi ... | 1987 | 3676814 |
| hormonal control of sexual and scent marking behaviors of male gerbils in relation to the sexually dimorphic area of the hypothalamus. | the sexual and scent marking behaviors of male gerbils are stimulated by testosterone (t) action in the preoptic area (poa) of the hypothalamus. the sexually dimorphic area (sda) in the posterior poa, which also responds to t, is implicated in this process. this research studied the sensitivities of mating, marking, and the sda to t metabolites and other steroids. experiment 1 focused on mating. male gerbils were implanted at castration with 2-mm silastic capsules containing t, dihydrotestostero ... | 1987 | 3666686 |
| steroid autoradiography of the sexually dimorphic nucleus of the preoptic area. | autoradiography was performed to determine if the neurons of the sexually dimorphic nucleus of the preoptic area (sdn-poa) in the adult rat accumulate estradiol (e2), testosterone (t), and/or dihydrotestosterone (dht). three days prior to steroid administration, adult male and female sprague-dawley rats were gonadectomized and adrenalectomized. animals were then given either [3h]t, [3h]e2, or [3h]dht through an indwelling jugular cannula. one hour later, animals were decapitated and brain sectio ... | 1987 | 3620937 |
| effect of gonadectomy and reposition of gonadal steroids on alpha-melanocyte-stimulating hormone concentration in discrete hypothalamic areas during a 24-hour period. | hypothalamic alpha-melanocyte-stimulating hormone (alpha-msh) was measured by radioimmunoassay in males after orchidectomy and after orchidectomy plus testosterone replacement, and in females after ovariectomy and after ovariectomy plus estradiol or progesterone, or estradiol and progesterone (ep) replacement. gonadectomy inverted the diurnal rhythm of the alpha-msh content observed in intact males in the medial basal hypothalamus (mbh) and preoptic hypothalamic area (poa), and produced a notabl ... | 1987 | 3614548 |
| potentiation of pressor response to angiotensin ii at the preoptic area in spontaneously hypertensive rat. | cardiovascular responses to angiotensin ii(aii) at the preoptic area (poa) were compared between normotensive wistar kyoto rat (wky) and spontaneously hypertensive rat(shr) by measuring blood pressure and heart rate under unrestrained, conscious state via a catheter implanted chronically into the abdominal aorta and by injection of drugs into poa through a chronic guide cannula. aii injected into poa at doses of 0.3 ng and 1 ng produced a dose-dependent pressor response, accompanied with a sligh ... | 1987 | 3613838 |
| neural control of male-like pseudocopulatory behavior in the all-female lizard, cnemidophorus uniparens: effects of intracranial implantation of dihydrotestosterone. | dihydrotestosterone was implanted directly into the brain of ovariectomized all-female cnemidophorus uniparens. only implants located in the anterior hypothalamus-preoptic area (ah-poa) induced male-like pseudocopulatory behavior. implants in other brain regions, including the ventromedial hypothalamus (vmh), failed to elicit mounting and intromission behavior. implants in the vmh also failed to elicit female-like receptive behavior. radioimmunoassay revealed no significant difference in circula ... | 1987 | 3610057 |
| in vitro measurements of cholinergic activity in brain regions of hibernating ground squirrels. | high affinity choline uptake (hacu) and choline acetyltransferase (chat) activity were measured in synaptosomal p2 fractions from four brain regions in a mammalian hibernator, the golden-mantled ground squirrel. the 14co2 evolution from [6-14c]glucose was also measured. comparisons were made across the euthermic (not hibernating) and hibernation state in synaptosomes from cortex (ctx), preoptic area and hypothalamus (poa/hyp), olfactory apparatus (oa), and hippocampus (hpc). hacu was significant ... | 1987 | 3607532 |
| modifications in alpha-msh concentrations in different hypothalamic areas during the estrous cycle in the rat. | the present experiments were undertaken to examine the pattern of alpha-msh during the estrous cycle in different hypothalamic areas and assess if during the whole estrous cycle the msh which arises from proopiomelanocortin (pomc) has the same concentrations pattern as msh from the dorso-lateral hypothalamus. msh concentration of the mediobasal hypothalamus (mbh), preoptic area (poa) and dorso-lateral hypothalamus (dlh) was measured using a specific radioimmunoassay. the rats were sacrificed eve ... | 1986 | 3604705 |
| modulation of aromatase activity by testosterone in transplants of fetal rat hypothalamus-preoptic area. | conversion of androgens to estrogens by neural aromatase appears to be a prerequisite for a variety of effects of androgens on brain function, including sexual differentiation. activity of aromatase is modulated by its substrate testosterone (t) in adult hypothalamus-preoptic area (hpoa), resulting in significantly higher levels in the male. perinatal sex differences in activity have also been observed in hypothalamus, poa and/or amygdala. however, it is not known if higher levels in the perinat ... | 1987 | 3594264 |
| [annual meadowgrass (poa annua l.) pollinosis. early spring pollinosis caused by grass pollens]. | 1987 | 3592992 | |
| hypothalamic monoamines and their catabolites in relation to the estradiol-induced luteinizing hormone surge. | monoamines and non-conjugated catabolites (serotonin (5-ht), 5-hydroxyindole acetic acid (5-hiaa), 3,4-dihydroxyphenyl-acetic acid (dopac), homovanillic acid (hva), 4-hydroxy-3-methoxyphenylethyleneglycol (mhpg), norepinephrine (ne), and dopamine (da] were measured in the medial basal hypothalamus (mbh) and preoptic area (poa) of ovariectomized (ovx) and ovx estradiol (e2)-treated rats using high-performance liquid chromatography with electrochemical detection. these e2 treatments were sufficien ... | 1987 | 3580869 |
| temperature activation of courtship behavior in the male red-sided garter snake (thamnophis sirtalis parietalis): role of the anterior hypothalamus-preoptic area. | adult male red-sided garter snakes (thamnophis sirtalis parietalis) received radio-frequency lesions prior to 17 weeks of low-temperature hibernation. animals found to have bilateral lesions of the anterior hypothalamus-preoptic area (ah-poa) failed to exhibit courtship behavior on emergence from hibernation. those individuals in which the major portion of the destruction was centered in the anterior poa also exhibited deficits in thermoregulatory behavior. animals that received unilateral lesio ... | 1987 | 3580125 |
| lesions in the preoptic area suppressed sexual receptivity in ovariectomized rats with estrogen implants in the ventromedial hypothalamus. | the objective of the experiment was to determine if electrolytic ablation of a portion of the preoptic area (poa) influenced the activation of female lordosis behavior by implants of estradiol benzoate in the ventromedial hypothalamus (vmh) of ovariectomized (ovx) rats. two weeks after ovariectomy, rats received either bilateral electrolytic lesions (2 ma for 10 sec in experiment 1, or 1 ma for 5 sec in experiment 2) in the poa, or sham lesions (all procedures except passage of current). on the ... | 1987 | 3567671 |
| morphological evidence that luteinizing hormone-releasing hormone neurons participate in the suppression by estradiol of pituitary luteinizing hormone secretion in ovariectomized rats. | morphological characteristics of lhrh neurons identified by immunocytochemistry were studied using light and electron microscopy in female rats in which estradiol was replaced at the time of ovariectomy ('pseudo-intact' rats) or 3 weeks after ovariectomy (long-term ovariectomized, estradiol-treated). while estradiol levels were equivalent in these two groups, the rise in lh after ovariectomy was prevented by the immediate administration in the pseudo-intact rats, while the augmented plasma lh le ... | 1987 | 3543719 |
| electrophysiological test of an amphiphilic beta-structure in lhrh action. | micropipettes were used to record electrical activity from single neurons in hypothalamic tissue slices, in the hypothalamic arcuate nucleus (arc), and in the periventricular and suprachiasmatic preoptic nuclei (poa). responses were measured following in vitro application of luteinizing hormone releasing hormone (lhrh), and two analogues: lhrh models 1 and 3. model 1 (pyroglu-his-trp-ser-phe-thr-ile-lys-ile-thrnh2) had amino acid substitutions in residues 5-10 designed to form an amphiphilic bet ... | 1986 | 3542630 |
| short photoperiod-induced gonadal regression: effects on the gonadotropin-releasing hormone (gnrh) neuronal system of the white-footed mouse, peromyscus leucopus. | the peroxidase-antiperoxidase method was used to determine quantitatively the effect of short photoperiod-induced gonadal regression on the immunoreactive gonadotropin-releasing hormone (gnrh) neuronal system of female peromyscus leucopus. in mice exposed to either long (16l:8d) or short (8l:16d) photoperiod, immunoreactive cell bodies were loosely organized into six groups: olfactory peduncle, diagonal band of broca, septum, preoptic area (poa), anterior hypothalamus (ah), and basal hypothalamu ... | 1986 | 3539214 |
| [occurrence of pancreatic tumor markers and diagnosis of small pancreatic tumors. 3). poa (pancreatic oncofetal antigen)]. | 1986 | 3537373 | |
| differential in vitro stimulation by naloxone and k+ of luteinizing hormone-releasing hormone and catecholamine release from the hypothalami of intact and castrated rats. | we compared the effects of an opiate receptor antagonist, naloxone (nal), on in vitro lhrh and catecholamine release from the medial basal hypothalamus-preoptic area (mbh-poa) of intact and castrated adult male rats. the mbh-poa (six per chamber) were perifused in vitro for 6 h. after 1 h of preincubation, basal lhrh, dopamine (da), norepinephrine (ne), and epinephrine (e) release were estimated in perifusates collected during the second and third hours. during the fourth hour, chambers were per ... | 1987 | 3536452 |
| elevated pancreatic oncofetal antigen levels measured by enzyme immunoassay in pure pancreatic juice of patients with pancreatic cancer. | pancreatic oncofetal antigen (poa) was measured by enzyme immunoassay in pancreatic juice from patients with pancreatic cancer, chronic pancreatitis, or other diseases. poa levels in pancreatic cancer were significantly higher than in other disorders, and poa was seen by immunofluorescence to be in the cancerous tissues of pancreatic cancer. assay of poa in the pancreatic juice may be more reliable than serum poa, and could contribute to the diagnosis of pancreatic cancer. | 1986 | 3531954 |
| effects of estradiol and progesterone on the gonadotropin-releasing hormone (gnrh)-immunoreactive neuronal system of the anestrous ewe. | the effects of treatment with estradiol-17 beta (e2) and progesterone (p4) on the neuronal system for gonadotropin-releasing hormone (gnrh) of the ovariectomized ewe during the non-breeding season were examined using immunocytochemical and radioimmunoassay analyses. the majority of gnrh-immunoreactive cell bodies are located in the medial preoptic area (poa). clusters of labelled cell bodies also are found in the septum and anterior hypothalamus. gnrh fibers projected from the medial poa to a de ... | 1986 | 3530378 |
| formation of behaviorally active estrogen in the dove brain: induction of preoptic aromatase by intracranial testosterone. | the preoptic area (poa) of the male ring dove is a target for specific behavioral effects of estrogen that are separable from those of androgen. activity of the aromatase system in the poa, which converts testosterone to 17 beta-estradiol (e2), is increased by systemic androgen. using crystalline steroid implants positioned stereotaxically in the brain, we examined whether aromatase induction is a result of direct steroid action on the poa, which can occur independently of the behavioral effects ... | 1986 | 3526169 |
| autonomic thermoregulation after separation of the preoptic area from the hypothalamus in rats. | to clarify the role of the hypothalamic preoptic area in autonomic thermoregulation, the preoptic area (poa) of rats was disconnected from the rest of the brain-stem by bilateral microknife cuts which spared or included the medial forebrain bundle. the animals' metabolic responses to exogenous norepinephrine (0.5 mg/kg, im) were then measured at ambient temperatures of 25 degrees and 15 degrees c. oxygen uptake and colonic and tail skin temperatures were also measured at ambient temperatures of ... | 1986 | 3520477 |
| relationships between sexual activity, plasma testosterone, and the volume of the sexually dimorphic nucleus of the preoptic area in prenatally stressed and non-stressed rats. | the sexually dimorphic nucleus of the preoptic area (sdn-poa) has recently been shown to be reduced in cross-sectional area in prenatally stressed male rats. as masculine copulatory behavior is also reduced in prenatally stressed animals, the present study was designed to test a possible relationship between the entire volume of the sdn-poa and masculine sexual activity in both prenatally stressed and control adult male rats. we report here that prenatally stressed adult males have significantly ... | 1986 | 3518858 |
| quantitative assessment of the synergistic and independent effects of estradiol and progesterone on ventromedial hypothalamic and preoptic-area proteins in female rat brain. | in this study, quantitative assessment of the synergistic and independent effects of estradiol and progesterone on protein synthesis in the ventromedial hypothalamus (vmn) and the preoptic area (poa) was accomplished using in vitro 35s-methionine and 35s-cystein labeling, two-dimensional gel electrophoresis, and computerized densitometry. ovariectomized (ovx) rats were divided into four groups. group 1 was implanted with estradiol (e) capsules for 6 hr and injected with progesterone (p; 0.1 ml, ... | 1987 | 3505342 |
| androgen receptors in brain and pituitary of female rats: cyclic changes and comparisons with the male. | the in vitro binding of a synthetic androgen, methyltrienolone ([3h]-r1881), to brain and pituitary (pit) cytosol and nuclear extracts was determined in male and female rats. purified cytosol was prepared from pit or hypothalamic-preoptic area-amygdala (hpa) and incubated in the presence of 0.1 to 10 nm [3h]-r1881. scatchard analysis revealed the presence of a single, saturable, high-affinity binding site in pit cytosol with a dissociation constant (kd) of 0.42 x 10(-10) m in females and 0.95 x ... | 1986 | 3485449 |
| organization of central hyperthermic mechanisms in helium-cold hypothermic hamsters. | we have investigated the ability of three hyperthermic stimuli (pge2, 5-ht and ach) to elicit hyperthermia in the helium-cold (he-cold) hypothermic hamster. hamsters in these conditions are poikilothermic and will passively follow room temperature in a regulated cold room. animals were injected centrally at ah/poa sites via an indwelling guide tube at body temperatures maintained between 9-12 degrees c. active sites in the ah/poa were determined prior to the experiment by pge2 injection. pge2 in ... | 1986 | 3463374 |
| [neurogenic stress gastric ulceration--an experimental study in rats]. | experimental investigation was performed on pathogenesis of neurogenic stress gastric ulceration, i.e. the gastric ulceration occurring under stress in individuals having brain lesions. male wistar rats, weighing 250 to 300 g, were divided into the following 4 groups: a) the normal group, b) the subarachnoid hemorrhage (sah) group, in which 0.2 ml of arterial blood had been injected into the cisterna magna 3 days before, c) the brain lesion group, in which various right hypothalamic nuclei had b ... | 1987 | 3431640 |
| triterpenoids and other components of poa huecu. | 1987 | 3430173 | |
| neuropeptide y (npy): a possible role in the initiation of puberty. | npy modulates the rat hypothalamic-pituitary-gonadal axis at both the adenohypophysial and central levels. previously published studies have consistently shown elevations of gnrh content in the preoptic area (poa) and hypothalamus starting with the appearance of gnrh immunoreactivity around fetal day 12-14 until stabilization around the time of puberty. in the present studies, irnpy content of male and female rat hypothalami and poa was examined during days 0 to 36 of postnatal development. hypo ... | 1988 | 3416829 |
| temperature-related release of serotonin from unrestrained rats' pre-optic area perfused with ethanol. | the circumscribed effect of ethyl alcohol on the local efflux of serotonin (5-ht) within the thermosensitive region of the anterior hypothalamic, pre-optic area (ah/poa) of the unrestrained rat was examined in relation to core temperature. a single guide cannula for push-pull perfusion was implanted stereotaxically in the ah/poa within coronal planes ap 7.0-8.2. following 3-4 push-pull perfusions with control artificial csf of a site identified as reactive to 5-ht, ethanol in a concentration of ... | 1988 | 3415763 |
| creep grazing and early weaning effects on cow and calf productivity. | one hundred fifty simmental-hereford cows and calves were used in a 3-yr study to evaluate three creep grazing treatments and an early weaning treatment on cow and calf performance during midsummer (july to september). calves were approximately 150 d of age and averaged 178.6 kg when treatments were initiated. tifleaf pearl millet (pennisetum americanum l. leeke) was used as the forage for two of the creep treatments, representing two cow stocking intensities of .466 (tlm1) and .239 (tlm2) ha of ... | 1988 | 3397337 |
| steroids induce hypothalamic progestin receptors and facilitate female sexual behavior in neonatal rats. | this report provides the first evidence that two activational actions of estrogen can occur within the first week of life in the rat. priming 4-day-old rats with exogenous estradiol benzoate facilitates lordosis and ear wiggling-like behavior, and induces cytosol progestin receptors in the medial basal hypothalamus and preoptic region (hyp-poa) 44 h later. moreover, unprimed male infants show more intense lordosis and higher concentrations of cytosol progestin receptors in hyp-poa than infant fe ... | 1988 | 3395857 |
| effects of endophyte-infected fescue on concentrations of prolactin in blood sera and the anterior pituitary and concentrations of dopamine and dopamine metabolites in brains of steers. | an experiment was conducted to determine if the decrease in circulating concentrations of prolactin in cattle consuming endophyte (acremonium coenophialum) -infected tall fescue (festuca arundinacea) was associated with changes in prolactin concentrations in the anterior pituitary and concentrations of dopamine (da) and its metabolites 3,4-dihydroxyphenyl-acetic acid (dopac) and homovanillic acid (hva) in the stalk median eminence (sme), preoptic area (poa) and hypothalamus (hp). six crossbred s ... | 1988 | 3378927 |
| neurotropic effects of estrogen on the neonatal preoptic area grafted into the adult rat brain. | the preoptic area (poa) or cerebral cortex taken from newborn female rats were transplanted into the third ventricle of ovariectomized adult rats. from the day of transplantation, estradiol-17 beta in a silastic capsule was implanted subcutaneously into host animals for 4 weeks. the poa or cerebral cortex transplants were examined at light- and electron-microscopic levels 4 weeks after transplantation. all of the poa or cortical grafts showed an appearance similar to normal neural tissue. estrog ... | 1988 | 3378263 |
| muscarinic receptors in preoptic area and hypothalamus: effects of cyclicity, sex and estrogen treatment. | cholinergic muscarinic receptor binding was measured in the preoptic area (poa) and whole hypothalamus (hth) of adult sprague-dawley rats using the tritiated antagonist quinuclidinyl benzilate ([3h]qnb) as the ligand. binding of [3h]qnb expressed as fmol/mg protein was 30% higher in poa than in hth from gonadectomized rats. cyclic changes were observed in the poa with the highest binding at proestrus and the lowest binding at diestrus. in hth, no significant changes occurred over the estrous cyc ... | 1988 | 3378147 |
| progesterone modulation of androgen receptors in the brain and pituitary of male guinea pigs. | androgen receptors (ar) were determined in cytosol and nuclear extracts of pituitary and neural tissue from intact male guinea pigs by a binding assay using [3h]dihydrotestosterone as ligand. saturation analyses of cytosol from hypothalamus-preoptic area (poa)-amygdala regions and anterior pituitary revealed receptors (arc) with apparent kd values of 2.52 and 3.83 x 10(-10) m, respectively. nuclear salt extracts from the same tissues contained receptors (arn) with kd values of 4.38 and 5.12 x 10 ... | 1988 | 3371256 |
| in-vitro pulsatile luteinizing hormone-releasing hormone output is dependent on hypothalamic region and the stage of the estrous cycle. | in the following experiments, the role of the preoptic-suprachiasmatic area (poa-scn) in the control of luteinizing hormone-releasing (lhrh) release was examined by in vitro superfusion of either mediobasal hypothalamus (mbh) or mbh-poa-scn fragments obtained from cycling rats killed on various days of the estrous cycle. the lowest level of lhrh output occurred during estrus, highest levels during diestrus, and intermediate levels on proestrus in the mbh-poa-scn preparation. as expected, signifi ... | 1987 | 3327540 |
| pregnanolone, a metabolite of progesterone, stimulates lh-rh release: in vitro and in vivo studies. | the effect of 5 beta- and 5 alpha-reduced progestins on luteinizing hormone-releasing hormone (lh-rh) release was examined using either an in vitro superfusion or an in vivo push-pull perfusion (ppp) technique. ovariectomized rats (at least 6 days post operation: ovx) were implanted subcutaneously in the neck region with a silastic capsule containing 17 beta-estradiol (235 micrograms/ml: e2). two days afterwards, these ovx + e2 rats were subjected to experimental conditions. pregnanolone(5 beta- ... | 1987 | 3325129 |
| immunohistochemical demonstration of prognrh and gnrh in the preoptic-basal hypothalamus of the primate. | an antiserum (ark-1) specific to the gonadotropin-releasing hormone precursor (prognrh) was produced by immunizing with a synthetic peptide (prognrh 6-16; gly-leu-arg-pro-gly-gly-lys-arg-asp-ala-glu) which bridges the proteolytic cleavage site of prognrh. when used in the radioimmunoassay, ark-1 bound 25% of the iodinated 5-16 fragment at a 1:30,000 dilution with a sensitivity of 1 pg/tube. using immunohistochemical techniques, we observed that in serial and the same sections through the preopti ... | 1987 | 3302746 |
| female sexual behavior in hypogonadal mice with gnrh-containing brain grafts. | hypogonadal female mice respond to gnrh-containing fetal preoptic area (poa) implants in the third ventricle with vaginal opening and persistent vaginal estrus, ovarian, and uterine development and increased gonadotropin secretion. when these females are mated with normal males, reflex ovulation results in pregnancy. in the present study, poa implants derived from neonatal pups, whether male or female, were also capable of supporting reproductive development in the hypogonadal female mice. evalu ... | 1987 | 3301619 |
| the effect of hyperprolactinemia produced by transplantable pituitary mttw15 tumor cells in male rats on hypothalamic luteinizing hormone-releasing hormone release in vitro: effects of naloxone and k+. | although hyperprolactinemia has been reported to decrease reproductive function in male rats, the mechanism of these effects is not fully understood. we examined the effects of chronic hyperprolactinemia and castration on the lhrh content of the medial basal hypothalamus (mbh) and on the basal and evoked in vitro release of lhrh from the mbh-preoptic area (poa). adult wistar-furth male rats were inoculated with mttw15 tumor fragments; 3 weeks later half of the rats were castrated. hyperprolactin ... | 1987 | 3297642 |
| peripubertal development of noradrenergic stimulation of luteinizing hormone-releasing hormone neurosecretion in vitro. | the effect of age on norepinephrine (ne) stimulation of luteinizing hormone-releasing hormone (lh-rh) secretion from preoptic area-mediobasal hypothalamic (poa-mbh) explants was examined in the present study. explants were obtained from juvenile (9-day-old), prepubertal (29-day-old) and adult female rats. following decapitation and surgical isolation, poa-mbh explants were individually perifused with culture medium which was collected for radioimmunoassay of lh-rh. explants were exposed to two p ... | 1988 | 3285962 |
| males increase progestin receptor binding in brain of female voles. | in female prairie voles, behavioral estrus is induced by exposure to an unfamiliar male and ovulation is induced by mating. experiments were conducted to determine whether a saturable high-affinity progestin binding site (prc) is present in cytosols of brain tissue from females exposed to male stimuli for a period of time which is sufficient to bring most females into heat. prc were detected in both the medialbasal hypothalamus (mbh) and preoptic area (poa). however, prc levels increased in resp ... | 1988 | 3285365 |
| facilitation of lordosis in female rats by cns-site specific infusions of an lh-rh fragment, ac-lh-rh-(5-10). | structural alterations of the luteinizing hormone-releasing hormone (lh-rh) molecule have been performed to yield analogs which are more potent than, or which compete with, the parent hormone to increase the release of lh from the pituitary gland. the effects of these analogs on mating behavior, however, do not always parallel their effects on lh release. the present study tested the effectiveness of a pituitary-inactive fragment of lh-rh, namely ac-lh-rh-(5-10), in potentiating mating behavior ... | 1988 | 3282608 |
| effects of prenatal alcohol exposure on the sexually dimorphic nucleus of the preoptic area of the hypothalamus in male and female rats. | prenatal alcohol exposure can produce a variety of behavioral and physiological alterations, including changes in sexually dimorphic behaviors. it has been proposed that alcohol alters these behaviors by altering prenatal androgen and/or other steroid levels. this study was designed to examine the effects of prenatal alcohol exposure on a sexually dimorphic neuroanatomical structure, namely, the sexually dimorphic nucleus of the preoptic area of the hypothalamus (sdn-poa). this nucleus is larger ... | 1988 | 3279861 |
| pattern differences in experimental fevers induced by endotoxin, endogenous pyrogen, and prostaglandins. | to distinguish pattern differences in experimentally induced fevers, we investigated febrile responses induced by intravenous (iv), intracerebroventricular (icv), and intra-preoptic/anterior hypothalamic (poa) administration of bacterial endotoxin (lipopolysaccharide, lps), endogenous pyrogen (ep), human recombinant interleukin-1 alpha (il-1), and prostaglandins e2 and f2 alpha (pge2 and pgf2 alpha). intravenous lps, ep, or il-1 in high concentrations caused biphasic fever. in low concentrations ... | 1988 | 3258478 |
| effect of prostaglandin e2 on thermoresponsive neurones in the preoptic and ventromedial hypothalamic regions of rats. | 1. we investigated the effect of microinjection of prostaglandin e2 (pge2) into the preoptic (poa) or the ventromedial hypothalamic (vmh) region on rectal temperature in rats. fever was induced by microinjection of pge2 into the poa or the vmh regions. the febrile responses induced by pge2 injected into the vmh region were significantly greater than those induced by injection into the poa region. 2. the effect of temperature on neuronal activity in the poa and the vmh regions was investigated by ... | 1988 | 3255803 |
| hippocampal serotonin mediates hypoactivity in dietarily obese hamsters: a possible manifestation of aging? | to determine whether endogenous opiates mediate hyperactivity in food restricted hamsters and serotonergic fibers innervating the hippocampus mediate hypoactivity in obese hamsters, food restriction and high-fat diet supplementation were used to produce significant body fat changes (8 vs. 21%). the levels and pattern of spontaneous running were examined after ip saline or naloxone hcl (20 mg/kg) and following the infusion of vehicle and 5,7-dihydroxytryptamine creatine sulfate (4 micrograms/2 mi ... | 1988 | 3252281 |
| effects of estradiol on secretion of lh, hypothalamic function and testicular development in bull calves. | two experiments were conducted in order to determine the effects of estradiol (e2) on the development of the hypothalamic-pituitary-testicular axis in bull calves. in experiment 1, calves were assigned randomly to one of the following groups: 1) intact, 2) intact e2-treated, 3) castrated, or 4) castrated e2-treated. treatments began when the calves were 7.5 wk of age and continued for 16.5 wk. samples of blood were collected once a week from 3 to 14 wk of age and every 10 min for 6 hr at 8, 12 a ... | 1988 | 3246147 |
| quantitative assessment of early and discontinuous estradiol-induced effects on ventromedial hypothalamic and preoptic area proteins in female rat brain. | in this study, changes in individual proteins in the ventromedial hypothalamus (vmn) and the preoptic area (poa) of the female rat brain were quantitatively assessed following either a short treatment (2 h) or a discontinuous schedule of estradiol. ovariectomized (ovx) rats were implanted with estradiol capsules or sham-implanted for the appropriate paradigm and sacrificed by decapitation. punches of brain tissue containing the vmn and poa were incubated with 35s-methionine and 35s-cysteine, and ... | 1988 | 3244404 |
| positive feedback in hypogonadal female mice with preoptic area brain transplants. | when fetal preoptic area (poa) brain grafts that contain gonadotropin-releasing hormone cells are transplanted into the third ventricle of adult female hypogonadal mice, the animals respond with sexual maturation, persistent estrus, and the ability to ovulate reflexively after mating. however, the absence of normal spontaneous ovulatory cyclicity suggests an impairment in positive feedback. we, therefore, studied the effect of administration of progesterone alone or of sequential estradiol benzo ... | 1988 | 3221980 |
| neural transection between preoptic area and septum inhibits maternal behavior in female and male rats. | artificially-induced maternal behavior was examined in inexperienced female and male rats following neural transection between the preoptic area and the septum. anterior roof deafferentation (ard) of the preoptic area (poa) was performed with an l-shaped microknife. virgin female and male rats with or without ard were exposed to the continuous presence of normal pups to induce maternal behavior 3 weeks after surgery. ard resulted in a significant delay of the onset of maternal behavior in female ... | 1988 | 3217053 |
| site-specific inhibition of receptivity by intracranial anisomycin in hamsters. | the ventromedial nucleus of the hypothalamus (vmh) has been implicated in the mediation of the hormonal control of female rodent sexual behavior. however, in hamsters, progesterone (p) has been found to have effects on sexual receptivity in other diencephalic and mesencephalic sites as well. progesterone is thought to exert its behavioral effects by altering protein synthesis in cns target neurons. we tested the effects of 30 gauge implants of the protein synthesis inhibitor anisomycin in the pr ... | 1988 | 3208146 |
| postnatal influence of diethylstilbestrol on the differentiation of the sexually dimorphic nucleus in the rat is as effective as perinatal treatment. | the volume of the sexually dimorphic nucleus of the preoptic area (sdn-poa) of the male rat brain is larger than that of the female. in the female rat, treatment with diethylstilbestrol (des), either perinatally (from day 16 of gestation to postnatal day 10), or postnatally (birth to day 10) was equally effective in increasing the volume of sdn-poa compared to controls. prenatal treatment (day 16 of gestation to birth) with des also increased the volume of the sdn-poa but this increase was signi ... | 1988 | 3208082 |
| pancreatic oncofetal antigen and carcinoembryonic antigen in breast and colon carcinoma. | pancreatic oncofetal antigen (poa) and carcinoembryonic antigen (cea) were determined in plasma of 195 patients with breast cancer and 90 patients with colon carcinoma. increased levels of poa and cea were seen in 19.0 and 25.6% of patients with breast cancer, respectively. some but not all patients showed an increase in both markers. the incidence of abnormal concentrations of poa and cea increased with the progress of the disease. poa appears to be a useful marker in breast cancer, especially ... | 1988 | 3206109 |
| isolation and characterization of poa p i allergens of kentucky bluegrass pollen with a murine monoclonal anti-lol p i antibody. | the poa p i allergens were isolated from the retentate fraction of a dialyzed preparation of an aqueous extract of kentucky bluegrass pollen by means of a reverse immunosorbent prepared with a murine anti-lol p i monoclonal antibody, mab 290-a-167. by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and preparative isoelectrofocusing, poa p i was found to consist of a 35.8-kd component with an isoelectric point of 6.4 and a 33-kd component with one of 9.1 and designated as poa p ia (ac ... | 1988 | 3203966 |
| hormonal modification of the number of total and late-arising neurons in the central part of the medial preoptic nucleus of the rat. | the sexually dimorphic nucleus of the preoptic area (sdn-poa) is larger in volume in males, is responsive to steroids developmentally, and contains a subpopulation of late-arising neurons that can be specifically labeled with 3h-thymidine on embryonic day 18 (e18). the cytoarchitecture of this region has been described, and one component, the central part of the medial preoptic nucleus (mpnc), shows considerable overlap with the sdn-poa. one goal of the present study was to relate the two by det ... | 1988 | 3192761 |
| estrogen/progesterone treatment in adulthood affects the size of several components of the medial preoptic area in the male rat. | the results of preliminary studies suggested that steroid and/or propylthiouracil (ptu) treatment of adult gonadectomized (gxd) male rats significantly reduced the volume of the sexually dimorphic nucleus of the preoptic area (sdn-poa). therefore, we designed a study to examine this effect in detail. groups of adult rats were sham gxd (intact) or gxd, then treated with multiple injections of oil (males and females), or estrogen and progesterone (males). gonadectomized estrogen/progesterone-treat ... | 1988 | 3192760 |
| cytoarchitectonic analysis of the sdn-poa of the intact and gonadectomized rat. | the densely staining group of cells referred to as the sexually dimorphic nucleus of the preoptic area (sdn-poa) is greater in volume in the male than in the female rat. because we and others have reported absolute volumes that have been consistent within individual studies but that vary considerably, we characterized the sdn-poa by describing its morphology with respect to the cytoarchitectonic divisions of the medial preoptic nucleus (mpn) in intact and gonadectomized rats. we report three maj ... | 1988 | 3192759 |
| [fluctuations in neuronal activity and sexual dimorphism in the medial preoptic nucleus of the hypothalamus during postnatal development of the rat]. | the medial preoptic nucleus of the hypothalamus of the rat is characterized by a sexual dimorphism of one of its substructures, the "sexually dimorphic nucleus of the preoptic area (sdn-poa)" (gorski et al. 1980), which becomes light microscopically visible at lower magnification. the sdn-poa, showing up as a concentration of perikarya, is principally larger in males than in females. furthermore, the sexual dimorphism of the medial preoptic nucleus is reflected in temporary significant differenc ... | 1988 | 3183360 |
| chronic morphine and testosterone treatment. effects on sexual behavior and dopamine metabolism in male rats. | the effects of sustained delivery of morphine and/or testosterone (t) on male rat copulatory behavior, penile reflexes and dopaminergic metabolism in selected brain regions were examined. castration was followed by (1) a decrease in the number of male rats exhibiting intromissive and ejaculatory behavior in mating tests, (2) decreased erections in ex copula tests, and (3) increases in dopamine and dihydroxyphenylacetic acid (dopac) concentrations in the mediobasal hypothalamus (mbh) and the preo ... | 1988 | 3173643 |
| [fundamental and clinical evaluation of irma for serum pancreatic oncofetal antigen (poa)]. | 1988 | 3164428 | |
| changes in photoperiod alter the daily rhythms of pineal melatonin content and hypothalamic beta-endorphin content and the luteinizing hormone response to naloxone in the male syrian hamster. | this study examines the possible involvement of beta-endorphin in the photoperiodic control of reproduction in the syrian hamster. beta-endorphin and lhrh concentrations in the medial basal hypothalamus (mbh), anterior hypothalamus (aha), and the preoptic area (poa) as well as pineal melatonin content were determined by ria in male syrian hamsters exposed to either a long day [(ld) 16-h light; 8-h dark; lights on 0700-2300] or short day [(sd) 8-h light, 16-h dark; lights on 0700-1500] for 8 week ... | 1985 | 3159563 |
| tissue polypeptide antigen, galactosyltransferase isoenzyme ii and pancreatic oncofetal antigen serum determination: role in pancreatic cancer diagnosis. | the clinical usefulness of tissue polypeptide antigen, galactosyltransferase ii and pancreatic oncofetal antigen was evaluated in detecting pancreatic cancer and in differentiating this malignancy from chronic pancreatitis and other diseases (mainly of the liver and biliary tract) which may enter in differential diagnosis. tpa seems to be the most sensitive among these indices in detecting pancreatic cancer and appears to discriminate this malignancy quite satisfactorily from chronic pancreatiti ... | 1988 | 3145303 |
| effects of hypothalamic lesions upon the sexual and social behaviour of the male common marmoset (callithrix jacchus). | the sexual and associated behaviour of 10 adult male marmosets was recorded during pair tests with ovariectomized females, before and after bilateral thermal lesions of the hypothalamus. four sham-lesioned males served as controls. lesions varied in volume from 1.49 to 3.28 mm3 and extended from the ventromedial hypothalamus to the diagonal band of broca. precopulatory behaviours (anticipatory erections, tongue flicking and anogenital investigations of the female) as well as frequencies of mount ... | 1988 | 3143470 |
| changes in dopamine activity in the zona incerta (zi) over the rat oestrous cycle and the effect of lesions of the zi on cyclicity: further evidence that the incerto-hypothalamic tract has a stimulatory role in the control of lh release. | previous results indicate that the dopaminergic system in the anterior medial zona incerta (zi) exerts a stimulatory effect on lh release. in this report changes in dopamine (da) turnover in the zi, preoptic area (poa) and arcuate/median eminence area (arc/me) (as assessed by the rate of decline in da concentration after alpha-methyl-p-tyrosine) have been noted each afternoon (16.00-18.00 h) of the 4 days of the oestrous cycle and also on the morning (9.00-11.00 h) of proestrus (p) and second da ... | 1988 | 3129140 |
| [modulating influence of stimulation of the preoptic area (poa) on pain-related neurons of the ventromedial nucleus of the hypothalamus (hvm) in rats]. | 1987 | 3126004 | |
| neural grafts and the restoration of pituitary and gonadal function in hypogonadal (hpg) mice. | the hypogonadal mouse is a mutant deficient in the hypothalamic gonadotrophic hormone releasing hormone (gnrh) with a consequent extreme depletion in pituitary luteinising hormone (lh) and follicle stimulating hormone (fsh) and a failure of post-natal gonadal growth. grafting late foetal-early neonatal preoptic area (poa) tissue into the third ventricle of adult hpg mice resulted in increased gnrh receptors in the pituitary, increased synthesis and secretion of lh and fsh, and full stimulation o ... | 1987 | 3124706 |
| role of the preoptic area in the neuroendocrine regulation of reproduction: an analysis of functional preoptic homografts. | in conclusion, poa grafts that contain gnrh cell bodies are capable of correcting many of the reproductive deficiencies that are associated with a genetic failure to produce gnrh. the previously infertile animals exhibit steroidogenesis and gametogenesis. ovulations associated with mating suggest that the grafted gnrh cells are responding to some environmental cues and may be under some regulation by the host brain. although the grafts contain tissue that may have sexually dimorphic characterist ... | 1986 | 3107453 |
| lesions of the sexually dimorphic nucleus of the preoptic area: effects upon lh, fsh and prolactin in rats. | bilateral lesions were placed in the sexually dimorphic nucleus of the preoptic area (sdn-poa) in castrated adult male rats in an attempt to determine a physiologic role for this nucleus. these lesions significantly attenuated the increase in plasma fsh and lh due to simultaneous castration at 24 hr, and at 7 and 14 days following surgery, and significantly decreased the levels of plasma prolactin on comparison with pre-operative values and those of castrated controls. when rats were castrated a ... | 1987 | 3103869 |
| para osteo arthropathy--ectopic ossification of healing tendon about the rodent ankle joint: histologic and type v collagen changes. | ectopic bone formation, or para osteo arthropathy (poa), is commonly seen in humans following lesions to the central nervous system. the condition also occurs after severe trauma, burns, or tetanus, and, rarely, after poliomyelitis or cauda equina lesions. the lack of a suitable laboratory animal model has hampered study of its etiology and treatment. the lesion occurs just above the rodent ankle joint 7 weeks after repair of the severed achilles tendon. tendon repair using a single silk suture ... | 1986 | 3094020 |
| slice cultures of lhrh neurons in the presence and absence of brainstem and pituitary. | luteinizing hormone releasing hormone (lhrh) neurons from the preoptic area (poa)/hypothalamus of the postnatal rat were cultured for up to 7 weeks using a slice explant roller culture technique. the slices thinned to quasi-monolayers, but maintained organotypic distributions of large numbers of immunocytochemically identifiable lhrh, neurotensin, tyrosine hydroxylase, neurophysin and corticotropin releasing hormone-containing neurons. the distribution, survival and morphology of lhrh cells in c ... | 1988 | 3072535 |
| luteinizing hormone-releasing hormone (lhrh) neurons in the male and female rats at peripubertal period. | luteinizing hormone-releasing hormone (lhrh) neurons were immunohistochemically studied in rats of both sexes at peripubertal ages. the number of immunoreactive lhrh neurons (irlhrh neurons) was counted in the brain region from the level of the septum-preoptic area to the level of the rostral part of the infundibulum in colchicine-treated male and female rats at 30 and 60 days of age. at 30 days, irlhrh neurons were more numerous in male rats than females. at 60 days, the number of irlhrh neuron ... | 1988 | 3066237 |
| effects of castration or testosterone implants upon pituitary function in hypogonadal mice bearing normal foetal preoptic area grafts. | grafts of normal mouse preoptic area (poa) tissue into the third ventricle of gonadotrophin-releasing hormone (gnrh)-deficient hypogonadal (hpg) mice resulted in an elevation of pituitary gnrh receptors, an increased synthesis of luteinizing hormone (lh) and follicle-stimulating hormone (fsh) by the pituitary gland, an elevation of gonadal lh receptors and in the stimulation of steroidogenesis and spermatogenesis in the testis. in normal mice both castration or the subcutaneous implantation of t ... | 1987 | 3035410 |
| hypothermia: role of alpha 1- and alpha 2-noradrenergic receptors in the hypothalamus of the cat. | the purpose of this study was to characterize the alpha 1- and alpha 2-noradrenergic receptor sub-types which could mediate the hypothermic response produced by norepinephrine (ne) and other alpha-noradrenergic agonists applied to the thermosensitive zone of the hypothalamus. an array of four guide tubes was implanted stereotaxically so that their tips rested just above the anterior hypothalamic, preoptic area (ah/poa) of the cat. following post-operative recovery, a micro-injection of an agonis ... | 1987 | 3033698 |
| dietary prevention of stroke and its mechanisms in stroke-prone spontaneously hypertensive rats--preventive effect of dietary fibre and palmitoleic acid. | previously it was reported that dietary protein, some amino acids and potassium are effective in preventing stroke in stroke-prone spontaneously hypertensive rats (shrsp). the present study revealed that other dietary factors could also prevent cerebral lesions, and the mechanism of this effect was studied. in shrsp given 1% nacl in their drinking water, a diet containing 10% active fibre (powdered brown seaweed converted to k+ form) significantly lowered blood pressure (bp) and markedly reduced ... | 1986 | 3023589 |
| diagnostic significance of cancer antigen 125, pancreatic oncofetal antigen, and carcinoembryonic antigen in malignant and tuberculous pleural effusions. | pleural fluid levels of cancer antigen 125 (ca 125), pancreatic oncofetal antigen (poa), and carcinoembryonic antigen (cea) were determined in 56 patients with malignant pleural effusion and in 35 patients with tuberculous effusion. malignant effusions had significantly higher pleural fluid ca 125 and cea levels than those of tuberculous origin (p less than 0.005). no significant difference in poa titers was found between the two kinds of effusion. assays of ca 125 and cea in pleural fluid may b ... | 1986 | 3009919 |
| the sex hormone-dependent development of opiate receptors in the rat medial preoptic area. | the opiate receptor content of the sexually dimorphic medial preoptic area (mpoa) was examined in newborn and 5-day old (d6) male and female rats. a significant increase of [3h]naloxone binding was observed in and around the sexually dimorphic nucleus of the preoptic area (sdn-poa) in d6 female rats, relative to newborn females. opiate receptor labeling did not increase over this period in males, nor was labeling different between males and females at birth. this dramatic alteration of mpoa opia ... | 1985 | 3000537 |
| synaptogenesis in the neonatal preoptic area grafted into the aged brain. | the medial preoptic area (poa) of newborn female rats was transplanted into the third ventricle of young adult (2 months of age) and aged (27 months of age) female rats. the grafted poa tissues were examined ultrastructurally 2 months after transplantation. the mean numbers of axodendritic shaft and spine synapses in the poa transplants in both young adult and aged female rats were much greater than those in the medial poa of newborn female rats. these results suggest that the neuronal substrate ... | 1985 | 2998555 |
| pituitary and gonadal function in hypogonadotrophic hypogonadal (hpg) mice bearing hypothalamic implants. | gnrh receptor values are 30-50% of normal in pituitaries of hpg male mice, and testicular lh receptors only 8% of normal (160.4 +/- 17.6 and 2013 +/- 208.1 fmol/testis respectively). in male hpg mice bearing fetal preoptic area (poa) hypothalamic implants for 10 days there was no change in pituitary gnrh receptors, pituitary gonadotrophin content, or seminal vesicle weight. however, testicular weights and lh receptors were doubled in 4/10 mice and 2 had increased serum fsh levels. between 26 and ... | 1985 | 2991511 |
| effect of delta 9-thc on brain and plasma catecholamine levels as measured by hplc. | the effects of chronic administration of delta 9-tetrahydrocannabinol (delta 9-thc) on the plasma and brain catecholamine (ca) levels were measured using high performance liquid chromatography-electrochemical detection (lc-ec) system. intact male rats were injected daily with vehicle (50 microliter oil) or with delta 9-thc (3 mg/kg body wt) over a period of 25 days. trunk plasma and tissue from preoptic area (poa) and mediobasal hypothalamus (mbh) were collected and catecholamine levels were det ... | 1985 | 2985210 |
| immunoreactive beta-endorphin concentrations in brain and plasma during pregnancy in rats: possible modulation by progesterone and estradiol. | changes in opioid concentrations in brain and plasma as well as opioid activity have been reported to occur as a function of pregnancy and lactation in rats. the present study examines the status and steroidal regulation of the endogenous opioid, beta-endorphin, in the behaviorally and neuroendocrinologically important preoptic area (poa) and hypothalamus, and in the plasma of pregnant and nonpregnant rats. in the first study, concentrations of beta-endorphin-like immunoreactivity (beta-ep-li-ir ... | 1987 | 2953986 |
| photoaffinity labelling of a thromboxane a2/prostaglandin h2 antagonist binding site in human platelets. | the diazonium salt of 9,11-dimethylmethano-11,12-methano-16-(4-aminophenoxy)13,14- dihydro-13-aza-15 alpha beta-omega-tetranor txa2 (pta-poa) was synthesized and used as a photoaffinity ligand for the putative human platelet txa2/pgh2 receptor. incubation of human platelet membranes with the diazonium salt of pta-poa followed by photolysis at 290 nm(hv) resulted in a 40% decrease in the specific binding of [125i]pta-oh as measured in the radioligand binding assay. co-incubation with a txa2/pgh2 ... | 1986 | 2946292 |
| pre- and postnatal influence of an estrogen antagonist and an androgen antagonist on differentiation of the sexually dimorphic nucleus of the preoptic area in male and female rats. | the volume of the sexually dimorphic nucleus in the preoptic area (sdn-poa) of the rat brain is severalfold larger in adult male rats than in adult females. this sex difference in brain structure was previously shown to develop under the influence of androgenic and estrogenic hormones during the perinatal period. we tried to clarify the differential role played by androgens and estrogens during development and differentiation of the sdn-poa by treating male and female rats during an extended pre ... | 1986 | 2939360 |
| experimental dissociation of hypothalamic functions: an analysis of neural structural components for prolactin release control in the male rat. | a review of the research work done in male rats regarding the possible anatomical substrate underlying the control of prolactin release is presented. also, a basis for the experimental dissociation of prolactin and lh release responses from a single brain locus is offered. it is proposed that the preoptic suprachiasmatic region (poa-sch) encompasses neural elements involved in the facilitation and inhibition of prolactin release: the dorsal aspect of this region seems to encompass predominantly ... | 1985 | 2938413 |
| actions of ru 38486 on progesterone facilitation and sequential inhibition of rat estrous behavior: correlation with neural progestin receptor levels. | the present study examined the actions of the antiprogestin ru 38486 on progesterone (p)-induced facilitation and sequential inhibition of estrous behavior and on brain cytosol progestin receptor (pr) levels in ovariectomized, estrogen-primed (0.5 micrograms of estradiol benzoate for 3 days) female rats. ru 38486 suppressed p-facilitated receptive and proceptive responses in a dose-dependent fashion when administered 1 hr prior to p. ru 38486 did not, however, block the sequential inhibitory eff ... | 1989 | 2925185 |
| prednisone pretreatment leads to histaminic airway hyporeactivity soon after resolution of the immediate allergic response. | we assessed the effect of prednisone pretreatment (50 mg/day for three days) on the development of the early increase in histamine reactivity that occurs soon after resolution of the immediate response in allergic humans. four allergic subjects who were known to develop only isolated immediate responses upon kentucky bluegrass inhalation, as well as four mild allergic asthmatic subjects known to develop typical dual phase responses, were evaluated. all testing was done more than nine weeks after ... | 1989 | 2914481 |
| sex differences in nuclear androgen receptors in guinea pig brain and the effects of an alpha 2 noradrenergic blocker on androgen receptors. | the binding of the synthetic androgen, [3h]methyltrienolone (r1881) to nuclear androgen receptors (nar) was studied in various brain areas of gonadectomized male and female guinea pigs treated for 3 days with 2 mg testosterone propionate. the scatchard analysis of salt-extracted nar showed a single, high-affinity receptor with a kd of 0.152 nm and maximum binding sites (bmax) of 161.9 fmol/mg dna. the concentration of nar was highest in the hypothalamus (hypo) and preoptic area (poa) in both mal ... | 1988 | 2905189 |
| transmitter and peptide actions on hypothalamic neurons in vitro: implications for lordosis. | this article summarizes a series of studies using brain tissue slices of rats to record single-unit activity from the hypothalamic ventromedial nucleus (vmn) and preoptic area (poa), both of which are crucial for the regulation of the estrogen-dependent feminine mating behavior, lordosis. in these studies the actions of acetylcholine (ach), serotonin (5ht), norepinephrine (ne), luteinizing hormone-releasing hormone (lhrh), arginine-vasopressin (avp), and oxytocin (oxy) on neuronal activity were ... | 1988 | 2900673 |
| photoperiodic adjustments in hypothalamic amines, gonadotropin-releasing hormone, and beta-endorphin in the white-footed mouse. | this study was undertaken to examine short photoperiod (sd; 8 h of light, 16 h of darkness)-induced alterations in reproductive endocrine and neuroendocrine parameters in the male white-footed mouse, peromyscus leucopus. exposure to sd for 8 weeks caused dramatic reductions in testis and seminal vesicle weights, decreased circulating lh and testosterone levels, and lowered the content of lh in the pituitary gland relative to those in mice under long photoperiod (ld; 16 h of light, 8 h of darknes ... | 1988 | 2899500 |
| development of hypothalamic neurons in intraventricular grafts: expression of specific transmitter phenotypes. | the anlages of the medial-basal hypothalamus (mbh), septopreoptic area (poa), rathke's pouch, and the parietal cortex (cc) of rats (at 12.5, 14.5 and 16.5 days of gestation) were transplanted singly or in combination into the third ventricle of adult female rats, and the development of neurons in the grafts was investigated immunohistochemically with the use of antisera to tyrosine hydroxylase (th), somatostatin (srih), acth, methionine enkephalin-arg6-gly7-leu8 (enk-8), rat corticotropin-releas ... | 1988 | 2895028 |
| rostral hypothalamus: a new neuroanatomical site of neurochemically-induced emesis in the cat. | the localized effect of noradrenergic agonists administered directly in the anterior hypothalamic preoptic area (ah/poa) in inducing emesis in the cat was investigated. of the noradrenergic agonists tested, which included norepinephrine, clonidine, phenylephrine and methoxamine, only clonidine in doses of 5.0-50.0 micrograms was found to evoke emesis consistently when micro-injected in a volume of 1.0 microliter into ah/poa of the unrestrained cat. the emetic response to clonidine was short-last ... | 1987 | 2889512 |