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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 ...19883255803
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 ...19883258478
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 ...19883279861
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 ...19883282608
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 ...19883285365
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 ...19883285962
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 ...19883371256
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 ...19883378147
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 ...19883378263
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 ...19883378927
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 ...19883395857
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 ...19883397337
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 ...19883415763
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 ...19883416829
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 ...19883129140
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 ...19883143470
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 ...19883145303
quantification of naloxone binding sites in brains from suckled beef cows during postpartum anestrus and resumption of estrous cycles.thirty beef cows, approximately 3 yr of age, were randomly assigned to be slaughtered on d 7, 14, 28, 42 or 56 postpartum. each cow suckled one calf until slaughter. data from cows slaughtered on d 42 and 56 were pooled and further classified as anestrous or cyclic based on the presence of a corpus luteum and elevated serum concentrations of progesterone at slaughter. specific binding of [3h]naloxone (3h-nal) to homogenates of tissue from hypothalamus (hyp), preoptic area (poa) and basal forebra ...19882837449
pituitary receptors for gnrh and estradiol, and pituitary content of gonadotropins in beef cows. ii. changes during the postpartum period.pregnant beef heifers (n = 24) were assigned randomly to four groups and slaughtered at day 1, 15, 30 or 45 postpartum. the day prior to slaughter blood samples were taken from each cow every 15 min for 8 hr. the anterior pituitary gland, preoptic area (poa) and medial basal hypothalamus (hyp) were collected from each cow. contents of gonadotropin-releasing hormone (gnrh) in extracts of poa and hyp, and luteinizing hormone (lh) and follicle-stimulating hormone (fsh) in extracts of anterior pitui ...19882852091
in vivo release rates of substance p in the preoptic/anterior hypothalamic area of ovariectomized and ovariectomized estrogen-primed rats: correlation with luteinizing hormone and prolactin levels.push-pull cannulae were implanted into the preoptic/anterior hypothalamic area (poa) of ovariectomized (ovx) rats. after recovery animals were treated with estradiol (e2) or corn oil and they were perfused 3 days later. substance p (sp) concentrations were measured in 15 min perfusate fractions, blood samples were taken at similar intervals. sp concentration in poa perfusates were readily measurable. following estrogen priming sp release increased significantly each afternoon prior to the estrog ...19882454436
androstenedione modulation of monoamine levels and turnover in hypothalamic and vocal control nuclei in the male zebra finch: steroid effects on brain monoamines.levels of norepinephrine (ne), dopamine (da), serotonin and the latter's primary metabolite, 5-hydroxyindoleacetic acid, were measured in two hypothalamic and 6 vocal control areas in the brains of male zebra finches. ne and da turnover in these areas were also estimated using alpha-methylparathyrosine. males were castrated for at least 3 weeks and then received an implant of androstenedione (ae) or a control implant of cholesterol. each male was then housed with a female for at least one week. ...19882460189
age-related changes in secretion of luteinizing hormone and metabolism of hypothalamic amines in bull calves prior to puberty.effects of age and castration on secretion of luteinizing hormone (lh) and metabolism of hypothalamic monoamines were determined in holstein bulls. calves were assigned to be intact or castrated and killed at 8, 12, or 24 wk of age. animals were castrated and bled every 10 min for 6 h at 96 and 24 h prior to slaughter, respectively. the stalk median eminence (sme), medial basal (mbh), and anterior-preoptic (aha-poa) hypothalamic regions were obtained at slaughter and assayed for norepinephrine ( ...19882461744
basal forebrain cholinergic and noncholinergic projections to the thalamus and brainstem in cats and monkeys.the projections of basal forebrain neurons to the thalamus and the brainstem were investigated in cats and primates by using retrograde transport techniques and choline acetyltransferase (chat) immunohistochemistry. in a first series of experiments, the lectin wheat germ-agglutinin conjugated with horseradish peroxidase (wga-hrp) was injected into all major sensory, motor, intralaminar, and reticular (re) thalamic nuclei of cats and into the mediodorsal (md) and pulvinar-lateroposterior thalamic ...19882466060
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 ...19882895028
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 ...19882899500
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 ...19882900673
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 ...19882905189
recognition of a site of a kentucky bluegrass pollen allergen by antibodies in the sera of allergic and non-atopic humans and a murine monoclonal antibody.allergen 27 was isolated from the aqueous extract of kentucky bluegrass pollen (kbg-r) with a reversed immunosorbent prepared by coupling murine monoclonal antibody, mab 27, to sepharose 4b. sera of patients allergic to kbg pollen, as well as serum of nonatopic individuals possessing anti-kbg antibodies, inhibited the binding of mab 27 to either ag 27 or kbg-r to the extent of 20 to 35% in elisa. in contrast, sera devoid of antibodies to kbg-r had no inhibitory capacity. in a radioallergosorbent ...19872434561
[tumor markers in hepatoma, gallbladder-biliary tract and pancreas cancer].possibilities for the early diagnosis of hepatoma, gallbladder-biliary tract cancer and pancreas cancer became getting higher by using method of monoclonal antibody. afp, gamma-gtp, hepatoma specific gamma-gtp, p-iii-p, pivka-ii and 5'-npd-v are sensitive and useful markers for diagnosis of hepatoma, ca 19-9 and cea for gallbladder-biliary tract cancer and pancreas cancer, and dupan-2 and poa for pancreas cancer. screening of sera of the patients with these tumor markers combined with image diag ...19872445292
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 ...19872889512
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, ...19873505342
triterpenoids and other components of poa huecu. 19873430173
[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 ...19873431640
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 ...19873607532
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 ...19873610057
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 ...19873613838
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 ...19873614548
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 ...19873620937
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 ...19873666686
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 ...19873676814
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 ...19873690294
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 ...19873690363
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 ...19873691063
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 ...19873297642
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 ...19873301619
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 ...19873302746
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- ...19873325129
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 ...19873327540
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 ...19873103869
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 ...19873033698
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 ...19873035410
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 ...19872953986
bronchial reactivity increases soon after the immediate response in dual-responding asthmatic subjects.to determine whether bronchial reactivity is augmented soon after an allergen-induced immediate asthmatic response, we compared reactivity to histamine before and immediately upon resolution of the immediate asthmatic response in seven subjects with mild asthma who were known to develop dual asthmatic responses after inhalation of kentucky bluegrass allergen. using a body plethysmograph and quiet breathing technique, specific airway resistance (sraw) and reactivity to aerosol histamine were asse ...19873792079
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 ...19873536452
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 ...19873543719
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 ...19873567671
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 ...19873580125
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 ...19873580869
[annual meadowgrass (poa annua l.) pollinosis. early spring pollinosis caused by grass pollens]. 19873592992
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 ...19873594264
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 ...19873124706
[modulating influence of stimulation of the preoptic area (poa) on pain-related neurons of the ventromedial nucleus of the hypothalamus (hvm) in rats]. 19873126004
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 ...19863604705
[occurrence of pancreatic tumor markers and diagnosis of small pancreatic tumors. 3). poa (pancreatic oncofetal antigen)]. 19863537373
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 ...19863539214
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 ...19863542630
prenatal androgen exposure, preoptic area and reproductive functions in the female rat.pregnant rats were injected with 4 mg of testosterone propionate (tp) from days 15 to 22 of pregnancy or a single dose of 4 mg tp on day 17 or 21 of pregnancy. female offspring treated with tp or the vehicle prenatally were sacrificed at 90 days of age. the volume of the cluster of intensely stained neurons in the medial preoptic area, the "sexually dimorphic nucleus of the preoptic area" (sdn-poa), was found to be affected by prenatal exposure to tp. the effect of tp on the development of the s ...19863799916
electrophysiology of limbic forebrain and paraventricular nucleus connections.the connections of forebrain structures with the hypothalamic paraventricular nucleus (pvn) were examined electrophysiologically in anaesthetized male rats. single unit recordings from 336 neurons were made within the cingulate cortex (cc, n = 78), lateral septum (ls, 114), bed nucleus of the stria terminalis (bst, 27). bed nucleus proprioris commissurae (bca, 27) and preoptic area (poa, 90). following pvn stimulation, some cells in all regions were identified as projecting to the pvn. antidromi ...19863801933
postnatal or in utero ethanol exposure reduction of the volume of the sexually dimorphic nucleus of the preoptic area in male rats.adult male rats exposed to alcohol in utero results in reduction of the volume of the sexually dimorphic nucleus of the preoptic area (snd-poa). reduction of the volume of this nucleus is also significantly reduced in rats exposed to ethanol postnatally compared to the volume in animals not exposed to ethanol (p less than 0.05). the results indicate that ethanol exposure during the postnatal period of brain development in rats is equally effective as in utero ethanol exposure in development of t ...19863803195
differentiation in male ferrets of a sexually dimorphic nucleus of the preoptic/anterior hypothalamic area requires prenatal estrogen.experiments were conducted to determine when during perinatal development testicular steroids act in ferrets to promote the organization of a bilateral nucleus in a medial position at the border of the preoptic area (poa) and anterior hypothalamus (ah), henceforth referred to as the male nucleus of the poa/ah (mn-poa/ah). the formation of the mn-poa/ah was promoted in female offspring by treating their mothers with testosterone over the last 11 days of the 42-day gestation period, whereas mn-poa ...19863808217
rate of in vivo verapamil exchange within the hypothalamus of the cat as examined by push-pull perfusion.to investigate the characteristics of the uptake within hypothalamic tissue of the ca2+-channel blocker, verapamil, push-pull canulae were implanted bilaterally above the anterior hypothalamic-preoptic area (ah/poa) and posterior hypothalamus (ph) of the cat. the functional reactivity of these two anatomical regions was verified in the unrestrained cat, prior to a push-pull perfusion, by a micro-injection of either 5-7 micrograms norepinephrine (ne) into ah/poa, or by perfusion of 50 mm ca2+ wit ...19863822047
reduction of the volume of the sexually dimorphic nucleus of the preoptic area by in utero ethanol exposure in male rats.ethanol consumption during pregnancy has been demonstrated to result in alterations in central nervous system structure and function. albino female rats were given either a liquid diet containing ethanol (5% w/v), a liquid diet which contained maltose-dextrin substituted isocalorically for the alcohol, or laboratory chow and water throughout pregnancy and for 14 days following birth. the volumes of the sexually dimorphic nucleus of the preoptic area (sdn-poa) and the nucleus accumbens septi (acn ...19863822241
kainic acid lesioning of the preoptic area alters positive feedback of estrogen in prepubertal female rats.stereotaxic infusion of kainic acid (ka) was performed to induce intrinsic neural lesions of the preoptic area (poa) in 25-day-old female rats. after ka infusion, rats in experiment 1 received 10 micrograms of estradiol benzoate (eb) administered subcutaneously to assess positive feedback of eb on release of luteinizing hormone (lh) from the pituitary gland. rats were perfused for light microscopic (lm) or electron microscopic (em) evaluation of the lesion site. rats of experiment 2 were allowed ...19863828436
sexual differentiation of the brain: a model for drug-induced alterations of the reproductive system.the process of the sexual differentiation of the brain represents a valuable model system for the study of the chemical modification of the mammalian brain. although there are numerous functional and structural sex differences in the adult brain, these are imposed on an essentially feminine or bipotential brain by testicular hormones during a critical phase of perinatal development in the rat. it is suggested that a relatively marked structural sex difference in the rat brain, the sexually dimor ...19863830102
stimulatory versus inhibitory effects of progesterone on estrogen-induced phasic lh and prolactin secretion correlated with estrogen nuclear and progestin cytosol receptor concentrations in brain and pituitary gland.the purpose of these studies was to determine the temporal requirements and time of day required for progesterone (p4) to amplify versus extinguish lh surges. the experimental animal model used in these studies was the 7-day ovariectomized rat (day 0) treated continuously with estradiol (e2) for 2-4 days (days 2, 3 or 4). in these studies we also examined the changes which occur in estrogen nuclear (ern) and progestin cytosol (prc) receptor concentrations in the preoptic area (poa), medial basal ...19863941760
a comparison between pyridinic and non-pyridinic extraction of allergenic materials.the effect of addition of pyridine in the extracting solvent of allergenic materials was studied in the following substances. dermatophagoides farinae, chenopodium album, parietaria judaica, phleum pratense, poa pratensis, and secale cereale. pyridinated extracts differed significantly in protein content, isoelectric focusing profile, and allergenic activity from the non-pyridinated extracts. on the other hand, no difference was detected between both extraction systems when their adsorption capa ...19863946840
sexual dimorphism in the preoptic/anterior hypothalamic area of ferrets: effects of adult exposure to sex steroids.the organization of neuronal cell bodies in the caudal preoptic area (poa) and rostral anterior hypothalamic area (ah) was studied in nissl-stained brain sections from adult male and female ferrets. computer-assisted image-analysis procedures were developed to help estimate the areas of cellular density and the sizes of individual perikarya. at the junction of the poa and ah, a bilateral dorsal-medial group of neurons was apparent only in male ferrets (dorsal nucleus). at the same coronal level, ...19863947970
effects of stimulation of the preoptic area on hypothalamic paraventricular nucleus unit activity and corticosterone secretion in freely moving rats.recordings were made of single unit activity through chronically implanted electrodes within the hypothalamic paraventricular nucleus of freely moving male rats also bearing chronically implanted stimulating electrodes in the preoptic area (poa) and indwelling jugular cannulae. high frequency electrical stimulation of the poa evoked increases in the rate of electrical discharge in 58% of the units tested. increases were recorded during each period of stimulation and were subsequently followed by ...19863951670
comparison of rostro-caudal brain stem influence on preoptic neurons and cortical eeg.the changes in activity of preoptic area (poa) neurons, and cortical eeg, upon stimulation of the caudal brain stem reticular formation (cbs) and the rostral brain stem reticular formation (rbs) are compared in this study. low frequency (lf) stimulation of the cbs (which induced eeg synchronization) and the rbs (which generally did not affect the eeg) had an excitatory influence on a majority of the affected neurons of the poa. in contrast, high frequency (hf) stimulation of the cbs (which produ ...19863955385
effect of ovarian steroids to stimulate region-specific hypothalamic 5-hydroxytryptamine synthesis in ovariectomized rats.accumulations of 5-hydroxytryptophan (5htp) and l-dihydroxyphenylalanine (l-dopa) following decarboxylase inhibition as indices for 5-hydroxytryptamine (5ht) and catecholamine (dopamine and/or norepinephrine) synthesis, respectively, were both increased in the preoptic area-anterior hypothalamus (poa-ah) of ovariectomized rats treated with a combination of 17 beta-estradiol benzoate (e2) and progesterone (p). similarly, an increased accumulation of l-dopa was seen in the mediobasal hypothalamus ...19863960276
monoamine biosynthesis in hypothalamic regions of dwarf mice: effect of replacement of deficient anterior pituitary hormones.female ames dwarf and phenotypically normal female mice were killed 30 min after treatment with nsd-1015, an aromatic l-amino acid decarboxylase inhibitor. the accumulation of dihydroxyphenylalanine (dopa) and 5-hydroxytryptophan were measured by high-performance liquid chromatography with electrochemical detection and provided estimates of the endogenous biosynthesis of dopamine (da) in the median eminence (me) and serotonin biosynthesis (5-ht) in all brain regions which were examined. dopamine ...19863960277
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 ...19862939360
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 ...19862946292
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 ...19863009919
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 ...19863023589
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 ...19863107453
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 ...19863094020
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%) ...19863698910
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 ...19863708321
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 ...19863719372
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 ...19863720878
[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 ...19863729433
effects of gonadectomy and androgen treatment on aromatase activity in the fetal monkey brain.we studied the ability of neural tissues from fetal rhesus macaques to aromatize androgens to estrogens and assessed whether androgens are involved in the regulation of aromatase activity during development. fetuses of both sexes, obtained on approximately day 100 of gestation, were gonadectomized and immediately given intraabdominal silastic capsules containing dihydrotestosterone. sham-gonadectomized (intact) and gonadectomized, sham-implanted groups were also studied. three weeks after the in ...19863741942
recovery of lordotic activity by dorsal deafferentation of the preoptic area in male and androgenized female rats.lordotic activity was examined in male and neonatally androgenized female rats following dorsal deafferentation of the preoptic area (poa). female pups were injected with various doses (100, 250, 500, or 1000 micrograms) of testosterone propionate (tp) on day 3 postpartum. ten weeks after birth, all animals were castrated, then half of the castrated males and females in each group were subjected to dorsal deafferentation of the poa (anterior roof deafferentation: ard) by using an l-shaped halász ...19863749307
electrophysiological evidence for an excitatory projection from ventromedial forebrain structures on to raphe- and reticulo-spinal neurones in the rat.spinally projecting neurones in nucleus raphe magnus (nrm) and the adjacent reticular formation of the medulla were identified by their antidromic responses to electrical stimulation in the lumbosacral spinal cord. identified raphe-spinal and reticulo-spinal neurones were then tested for the effects of electrical stimulation at sites in the ventromedial forebrain, including the anterior hypothalamus and preoptic area (ah/poa). the results of these experiments have demonstrated that a considerabl ...19863756468
effects of marginal selenium deficiency and winter protein supplementation on growth, reproduction and selenium status of beef cattle.seventy-two hereford x simmental cows, averaging 498 kg in body weight and 5.2 yr of age, were used in a 2-yr study to ascertain if selenium (se)-vitamin e (e) injections and winter protein supplementation would affect growth, reproduction and health of beef cattle maintained year-round on feedstuffs marginally deficient in se (.03 to .05 mg/kg). cows received either no injection or a mixture of 30 mg se (as sodium selenite) and 408 iu e injected subcutaneously beginning 3 to 4 mo prepartum and ...19863759693
elevated csf osmolality inhibits thermoregulatory heat loss responses.the effect of intracerebroventricular (icv) infusions of hypertonic nacl or sucrose on thermoregulatory responses to heat was studied in conscious rabbits to test the idea that brain osmoreceptors are involved in the inhibition of evaporative heat loss and elevation of body temperature in dehydrated mammals at high ambient temperature (ta). in rabbits hydrated ad lib and resting at a ta of 33 degrees c, icv infusion (3.4 microliter/min) of hypertonic (1,500 mosm) nacl or sucrose in artificial ce ...19863766775
effects of short days on aromatization and accumulation of nuclear estrogen receptors in the hamster brain.exposure of hamsters to short days increases sensitivity to the negative feedback effects of testosterone (t) but decreases responsiveness to the behavioral effects of the hormone. since t is metabolized in the brain to 5 alpha-dihydrotestosterone (dht) and estradiol, which differentially affect gonadotropin secretion and sex behavior, it is reasonable to postulate that daylength can modulate neural responses by quantitative or qualitative alterations in t metabolism and subsequent receptor bind ...19863768455
neuroanatomical mapping of hypothalamic regions mediating verapamil hyper- and hypothermia in the cat.guide cannulae for microinjection and push-pull perfusion in the unrestrained cat were implanted bilaterally in the anterior hypothalamic, preoptic area (ah/poa) and posterior hypothalamus (ph). postoperatively, the region was first identified in ah/poa which was reactive to norepinephrine or in ph to excess ca++ ions; in both cases a hypothermic response was produced. then either an artificial csf control vehicle or the ca++ ion channel blocking agent, verapamil, was perfused for 30 min by mean ...19863768734
[studies on a pancreatic oncofetal antigen (poa) in patients with pancreatic cancer].an enzyme immunoassay for poa prepared by gelder et al. was developed in our laboratory. elevated serum poa levels were shown in 70.6% (36/51) of patients with pancreatic cancer. poa levels were related neither to the stage nor to the degree of differentiation of pancreatic cancer. although poa levels were not elevated in patients with benign diseases of the pancreas, they were elevated in patients with cancer of the hepato-biliary tract. in pancreatic cancer patients with pre-operative high poa ...19863785134
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