stereotyped behavior and hyperthermia in dogs: correlation with the levels of amphetamine and p-hydroxyamphetamine in plasma and csf.a gas-chromatographic method for simultaneously measuring p-hydroxyamphetamine (poa) against amphetamine (a) in plasma and csf is presented. the time course of body temperature (tb), stereotyped behavior (st), and a and poa levels in plasma and csf were studied after administration of 0.6 and 1.5 mg/kg p.o. of a to dogs. stereotyped behavior reached maximal value 2.5 h after a, as did levels of a in csf. the a levels in csf decreased steadily in the following hours and simultaneously with the le ...197897724
further studies on the effects of lesions in the rostral hypothalamus on gonadotropin secretion in the female rhesus monkey (macaca mulatta).bilateral radiofrequency lesions were stereotaxically placed in the rostral hypothalamus of four adult female rhesus monkeys. these lesions resulted in extensive destruction of the ventromedial preoptic-anterior hypothalamic area (poa-aha) and included the suprachiasmatic nucleus as well as, with the exception of one animal, the organum vasculosum of the lamina terminalis. in three of these four animals, gonadotropin surges similar to those observed before surgery were elicited in response to ei ...1979110581
3h-estradiol distribution in female, androgenized female, and male rats at 100 and 200 days of age.tissue distribution of radioactivity was studied 48 h after gonadectomy and 1 h after iv injection of 3h-estradiol (1 mug/kg body wt) in 100- and 200-day-old normal female rats, female rats androgenized with 30, 100 or 1250 mug testosterone propionate (tp) at 5 days of age, and male rats. receptor-mediated uptake of estradiol, as shown by diethylstilbestrol (des) competition, was highest in preoptic area-anterior hypothalamus (poa-ah) and median eminence-basal hypothalamus (me-bh), but also occu ...1975163737
blockade of progesterone-induced increase in hypothalamic luteinizing hormone-releasing hormone levels and serum gonadotropins by intrahypothalamic implantation of 6-hydroxydopamine.the present study was undertaken to identify the hypothalamic locus where norepinephrine (ne) nerve terminals communicate with luteinizing hormone-releasing hormone (lh-rh)-containing neurons involved in the stimulatory feedback action of gonadal steroids on lh and fsh release. ovariectomized rats received estradiol benzoate (10 microgram/rat s.c.) on day 0. intracranial implants containing either 6-hydroxydopamine (6-ohda), to destroy ne terminals, or cocoa butter (controls) were placed bilater ...1979223726
nitrogen fixation associated with 'park' kentucky bluegrass (poa pratensis l.).associative nitrogen fixation in kentucky bluegrass (poa pratensis l.) turfs inoculated with five nitrogen-fixing bacterial isolates was evaluated using the acetylene reduction assay and nitrogen accumulation as indicators of fixation. 'park' and 'nugget' kentucky bluegrass turfs were grown in controlled environment chambers and inoculated with klebsiella pneumoniae (w-2, w-6, and w-14), erwinia herbicola (w-8), and enterobacter cloacae (w-11). 'park' inoculated with k. pneumoniae (w-6) had sign ...1979394819
quantitative assessment of para-osteo-arthropathy and its maturation on serial radionuclide bone images.paraplegics whose range of motion is limited by para-osteo-arthropathy (poa) may have difficulty in becoming independent unless the heterotopic bone mass is removed. the recurrence rate is high if the bony mass is not mature at the time of surgery. radiography and alkaline phosphatase correlations are not trustworthy. in 3 paraplegics with poa, radiolabeled osteotropic agents demonstrated a steady decrease in the uptake ratio (heterotopic/normal bone) followed by a steady-state plateau, reflecti ...1977403570
involvement of catecholaminergic nerve fibers in angiotensin ii-induced drinking in the japanese quail, coturnix coturnix japonica.monamine distribution in a septohypothalamic area was investigated in the japanese quail using a histochemical fluorescence method. this area includes the subfornical organ (sfo) and the preoptic area (poa) which are inferred dipsogenic receptor sites for angiotensin ii (aii) in the japanese quail. nerve fibers showing yellow-green fluorescence were found between the poa and the sfo. thwy traversed from the poa to the sfo, and some fibers seemed to terminate on the neurons in the sfo. after a lo ...1979487128
sensitivity of anterior hypothalamic areas to gonadal steroid implantation in androgenized female rats.a single injection of 1 mg of a complex of testosterone esters on day 5 of life was used to prepare constantly oestrous rats. such androgenized female rats were then ovariectomized and submitted to stereotaxical implantation of 1 microgram oestradiol benzoate, 5 microgram testosterone isobutyrate or, as a control, 10 microgram cholesterol in the anterior hypothalamic areas. the effects of the steroids on plasma and pituitary fsh and lh were assessed by radioimmunoassay. as reported previously by ...1977561152
luteinizing hormone secretion in hemidecorticate female rats under several experimental conditions.luteinizing hormone (lh) secretion by the anterior pituitary gland was investigated in hemidecorticate (hd) rats under several conditions. higher plasma and lower pituitary lh levels were observed in hd rats in the afternoon of proestrus, after unilateral ovariectomy, and at the 7th and 14th days after bilateral castration. the ovarian hypertrophy observed in hd rats did not differ from control. when hormonal substitutive therapy was started 3 days after bilateral ovariectomy, larger doses of es ...1978567287
preoptic-hypothalamic control of lh and prolactin release in male rats under pentobarbital anesthesia: differential responses to electrical acute experiments under pentobarbital anesthesia, the brains of adult male rats were stimulated bilaterally with trains of monophasic pulses at different frequencies and current intensities through bipolar, concentric, stainless steel electrodes. stimulation of the poa-sq region at 3, 10 (200 mua) or 200 hz (100 mua) increased plasma prolactin levels within 30 min of the onset of stimulation. stimulus parameters fully effective when applied to the poa-sq or arc-med. em. regions were ineffecti ...1978638765
[relationship between the skin test and the specific ige (radio-allergo-sorbens test) in the diagnosis of inhalative allergies].immediate-type reactions such as asthma, pollinosis and several forms of urticaria can be regarded as type i reactions according to coombs and gell. primary these diseases are caused by the immune globulin e. as skin testing is accompanied by numerous failors, there is a real possibility in increasing the diagnostic relevance by measurement of the specific ige in serum (radio-allergo-sorbens-test = rast; phadebas-rast -- pharmacia uppsala). there are often found divergent results and therefore t ...1977842065
new technique of injection of estradiol into preoptic-anterior hypothalamic area of newborn rats: technique limiting diffusion and duration, with preliminary results on postpuberal block of ovulation.previous studies have shown that sc administration of androgen or estrogen into newborn female rats will disturb postpuberal ovulatory function, as evidenced by a higher incidence of vaginal estrus, few ovarian corpora lutea, and the abolition of estrogen-induced luteinizing hormone surges after ovariectomy and chronic estrogen maintenance. studies of the uptake of labeled estrogen and intracerebral lesion studies have indicated the preoptic area and anterior hypothalamic nuclei (poa-ah) as poss ...1977401032
paradoxical effect of amphetamine in an endogenous model of the hyperkinetic syndrome in a hybrid dog: correlation with amphetamine and p-hydroxyamphetamine blood levels.a telomian-beagle hybrid has been studied as a possible model for the hyperkinetic syndrome in children. behavior tests showed that hybrids, like children, exhibit hyperactivity, impulsiveness, and impaired learning. two groups of hybrid could be differentiated; the behaviour of one improved after amphetamine (responders) while that of the other did not (nonresponders). moreover hybrids were less responsive than beagles to other effects of amphetamine such as stereotyped behaviour and hypertherm ...1979111287
the anterior hypothalamus: how it affects gonadotropin secretion in the rhesus monkey.the effects of hypothalamic lesions on spontaneous and estrogen-induced lh release were studied in 17 female rhesus monkeys with regular menstrual cycles. in the cycle before surgery, all of the animals experienced 3- to 10-fold increases in serum lh and elevated (above 3 ng/ml) serum concentrations of progesterone. three to 6 days after the onset of menstruation, lesions were made in the preoptic-anterior hypothalamic area (poa-aha) in 14 monkeys by radiofrequency thermocoagulation (rf) or by t ...1976820548
[plant antigens with immunological properties. ii. further studies of the chemical characteristics and immunological properties of a grass pollen extract].this second study carried out on an extract of two grass pollens (poa pratensis and phleum pratense) demonstrated the presence of n-acetilglucosamine and sialic acid in the extract (rfex). moreover the extract has confirmed its characteristics biologic activity i.e. the inhibition of the phenomenon of immune hemolysis with a different technique too, even having the antibodies of the treated animals the complement fixing activity. no appreciable changes of the immunoelectrophoresis pattern in the ...1976973743
effects of hypothalamic and preoptic lesions on reproductive behavior in male male rats, which were selected on the basis of showing complete patterns of male copulatory behavior on two prior tests, were castrated six weeks prior to brain surgery. animals were divided into three groups and given small bilateral lesions in the dorsomedial preoptic area (poa), ventromedial hypothalamus (vmh), or sham operations. starting 10 days postsurgery, all animals were injected with estrogen alone and estrogen plus progesterone, and tested twice for lordosis behavior. ten days f ...1977880486
tissue levels of luteinizing hormone-releasing hormone in the preoptic area and hypothalamus, and serum concentrations of gonadotropins following anterior hypothalamic deafferentation and estrogen treatment of the female rat.female rats were ovariectomized prior to anterior hypothalamic deafferentation (ahd) or sham ahd of the medial basal hypothalamus (mbh). lhrh in the mbh and the preoptic area (poa), and the blood concentrations of lhrh, fsh, and lh were measured following decapitation at the end of 30 days in experiment 1 and 28 days in experiment 2. interruption of anterior neural links of the mbh resulted in a drastic reduction in the amounts of lhrh in the mbh and a significant increment in the poa. the circu ...1976780098
fever produced by intrahypothalamic pyrogen: effect of protein synthesis inhibition by the unrestrained cat, the inhibition of protein synthesis by anisomycin, given either subcutaneously (5.0--25.0 mg/kg) or directly into the anterior hypothalamic, preoptic area (1.0--25.0 micrograms) impaired the development of a bacterial fever. s. typhosa infused intravenously (1:10 dilution in 1 ml) or into ah/poa (1.0 microliter) evoked an intense fever which was either significantly delayed or prevented by anisomycin. conversely, anisomycin failed to affect the typical hyperthermia evoke ...1979526856
hypothalamic injection of cycloheximide in the 4-day cyclic rat. acute suppression of lordotic behavior and ovulation.the results of serveral studies imply that estrogen can act upon the central nervous system via a protein synthetic step. our objective was to determine if the intrahypothalamic (preoptic area, poa) injection of cycloheximide (chx), an inhibitor of protein synthesis, at 17.00 h on diestrus ii of the 4-day cycle altered lordotic behavior and (or) ovulation in the intact rat (sexual receptivity to males normally begins on the evening of proestrus as herein defined; ovulation occurs on estrus of th ...1979514453
changes in the nuclear volume of rat hypothalamic neurons in old age.nuclear volumes (nv) of neurons in the preoptic are (poa), suprachiasmatic nucleus (sc), paraventricular nucleus (pvn), supraoptic nucleus (so), anterior hypothalamic area (aha), arcuate nucleus (arn), ventromedial nucleus (vmn), dorsomedial nucleus (dmn) and lateral mammillary nucleus (ml) were measured in 3.5- to 5-month-old female and male rats and in old female and male rats over 22 months of age. young adult female rats had larger nv than males in the neurons of all measured areas except fo ...19761018731
effect of prostaglandin, pyrogen and noradrenaline, injected into the hypothalamus, on thermoregulation in newborn lambs.thirteen newborn lambs were implanted stereotaxically with an array of 4 guide tubes positioned bilaterally so that their tips lay above various hypothalamic loci. at postnatal ages 50-70 h, rectal temperature was monitored, and bilateral 1 microliter injections were made into the hypothalamus. prostaglandin e1 (0.2 microgram) and prostaglandin e2 (0.2-2.0 microgram) did not cause fever on any occasion though injections were made into 44 sites throughout the hypothalamus. nevertheless, lambs tha ...1977884495
dynamic changes in hypothalamic lh-rh levels associated with the ovarian steroid-induced gonadotrophin lh surges were induced by treating ovariectomized rats (day 0) with either oestradiol benzoate (oeb, 40 micrograms/rat) or oestrogen (10 micrograms/rat followed by progesterone (4 mg/rat, day 2, oebp). to characterize the temporal changes associated with the lh surge on day 2, lh-rh levels in the medial basal hypothalamus (mbh) and the pre-optic area (poa) were analyzed by ria in rats sacrified at hourly intervals between 10.00--19.00 h. following these treatments the lh-rh con ...1979386683
direct septo-hypothalamic projections in the rat.axonal projections from neurons located in the medial and lateral septal nuclei (msn and lsn) were traced autoradiographically. the msn projected bilaterally via a midline route to the diagonal band of broca (dbb), the preoptic area (poa), the suprachiasmatic (scn), paraventricular (pvn), ventromedial (vhm) and arcuate (arc) nuclei including the median eminence (fiberous zone). lateral coursing fibers traveled with the medial forebrain bundle (mfb) to the supraoptic (son) and pre- and supra-mamm ...1979313542
responses and pharmacological properties of preoptic/anterior hypothalamic neurones following medial forebrain bundle stimulation.1. the responses of neurones in the anterior hypothalamic and preoptic areas (poa/aha) to stimulation of the medial forebrain bundle (mfb) have been studied in urethane anaesthetized female rats. extracellular unit recordings have been made from 150 neurones which were responsive to a single stimulus applied to the mfb at the level of the mammillary nucleus. 2. forty-five per cent of these cells were orthodromically activated with latencies ranging from 7.5 to 100 msec. however, the majority of ...1978307601
metabolism of siduron in kentucky bluegrass (poa pratensis l.). 19751133302
survival of ancylostoma caninum on bluegrass pasture.the survival of infective larvae of ancylostoma caninum on outdoor grass plots was studied in 40 experiments over 1 year. weather data were collected over the period. mean larval survival from august to early november was 24 days (range 1 to 49), from december through february was 0 days, and from march to mid-august was 6.6 days (range 0 to 21). moderate to high temperatures and substantial rainfall favored larval survival; low temperatures and rainfall favored larval destruction.19751138040
studies on hypothalamic estradiol binding during estrous cycle and after ovariectomy.specific binding of 3h-estradiol (1 microgram kg-1 injected s.c. 1 h before sacrifice) in the hypothalamus, anterior pituitary and uterus of cycling and ovariectomized female rats was investigated. preoptic-anterior hypothalamic area (poa-ah) and median eminence-basal hypothalamus (me-bh) were separated by gross dissection from the bulk of hypothalamus. pieces of parietal cortex served as controls. the lowest amount of 3h-estradiol specifically bound to cytoplasmic and nuclear receptors in poa-a ...1977305342
high density lipoprotein (hdl) polymorphisms in rabbit. i. a comparative study of rabbit and human serum high density lipoprotein.different classes of rabbit serum lipoprotein were prepared by ultracentrifugal flotation at densities 1-006, 1-063 and 1-21 g/ml. agarose gel electrophoresis on rabbit whole serum and the serum fractions with different densities showed that this technique separates the different lipoprotein classes reasonably well. the electrophoretic mobility of the different lipoprotein classes of rabbit serum seems to be similar to that of the human lipoproteins, with the exception of alpha1-lipoprotein whic ...1976180184
electrophysiological and pharmacological studies of amygdalo-hypothalamic connections in the rat.electrophysiological techniques have been used to investigate the neural connections between the amygdala and the rostral hypothalamus of female rats. recordings have been made from 120 neurones in the preoptic/anterior hypothalamic area (poa/aha) which could be driven by electrical stimulation of the amygdala. 89% of the neurones were activated orthodromically and, of these, 2 groups have been distinguished according to the latency of the responses. the remainder of identified cells were antidr ...1977909625
diagnostic value of total ige and antigen specific ige using rast in pollenosis.41 patients with clinically demonstrated pollinosis are studied. the following test were performed on all of them: a) intradermal skin tests using grass pollen extracts (pangramin iii) and with extracts of dactylis glomerate, lollium perenne and poa pratensis. b) totol serum ige determination. c) antigen specific ige (rast) determination against the pollens mentioned in b). d) passive hemagglutination against the pollen dactylis glomerate. basing on the results obtained, we have arrived to the f ...19751180203
cardiovascular changes in anaesthetised rats after the intra-hypothalamic administration of adrenaline.bilateral injections of adrenaline (0.01-10.0 microgram) into the anterior hypothalamic (ah) region, in urethane-anaesthetised spontaneous hypertensive (sh) rats, elicited dose-dependent falls in blood pressure and heart rate. the bradycardia was immediately in onset while the hypotension was preceded by a short-lasting rise in blood pressure. bilateral injections of adrenaline into the anterior preoptic area (poa) and areas surrounding the ah had little or no effect on blood pressure and heart ...1978755652
independent masculinization of neuroendocrine systems by intracerebral implants of testosterone or estradiol in the neonatal female rat.small pellets of testosterone (t) or estradiol (e2), but not cholesterol (ch), when implanted into the brain of neonatal female rats on day 2 or day 5 of life, produce masculinization of the adult regulation of gonadotropic hormone (gth) release, female sexual behavior or masculine sexual behavior, specific to the site and time of implantation and the hormone implanted. site specificity: there appear to be specific neuronal sites where implantation of t or e2 produces independent masculinization ...1978647393
regional and subcellular [3h]estradiol localization in selected brain regions and pituitary of female mice: effects of unlabeled estradiol and various anti-hormones.groups of ovariectomized mice were pretreated for 30 min with either vehicle, unlabeled estradiol benzoate or one of the following anti-hormones: cyproterone acetate, ci-628 or cn-69, 725-27. one hour after an i.v. injection of [3h]estradiol the levels of toluence extractable radioactivity retained in the crude nuclear and cytosol fractions of selected brain regions, pituitary and plasma were determined by liquid scintillation spectrometry. the major findings were: (1) in vehicle treated animals ...19761260424
intracranial cycloheximide: effect on male mouse sexual behavior and plasma testosterone.cycloheximide (cyclo), an inhibitor of protein synthesis, infused bilaterally into the preoptic area (poa) of intact b6d2f male mice significantly inhibited male sexual behavior when the males were presented with receptive females 12 hr after treatment. the few males that ejaculated appeared to copulate normally. this finding suggests that cyclo acts primarily by inhibiting sexual arousal rather than sexual performance. the inhibition of sexual behavior was not observed when the males were teste ...19761265105
activation of feminine sexual behavior in castrated male rats by intrahypothalamic implants of estradiol benzoate.the effects of intracerebral estradiol benzoate (eb) implants upon lordosis behavior in castrated male rats were investigated. 27 guage eb-filled or blank implants were placed unilaterally in either the preoptic area (poa) or the region of the ventromedial hypothalamic nucleus (vmh). when 0.5 microgram of eb was administered subcutaneously for eight days, males with eb implants had significantly higher lordosis quotients (lq) than males with blank implants. eb implants located in the region of t ...1979571538
influence of midbrain stimulation on the excitability of neurons in the medial hypothalamus of the rat.extracellular action potentials were recorded from 1098 neurons in the medial hypothalamus of pentobarbital anesthetized male rats. their excitability was analyzed after single 1 hz stimulation of the midbrain periaqueductal gray (pag) or adjacent reticular formation. cells were also examined for their response to median eminence (me), amygdala, lateral septum (ls) or anterior hypothalamic/preoptic area (aha/poa) stimulation. antidromic invasion from midbrain stimulation was recorded from 110 ne ...1979487122
gender and sexual orientation in relation to hypothalamic structures.animal experiments have provided evidence for the presence of sex differences from the synaptic level up to behaviour. although sex differences in the human brain may have been presumed implicitly since the days of aristotle, research on the presence of functional and structural sex differences of the human brain started only relatively recently. the most conspicuous sex difference in the mammalian brain was described by gorski et al. [1978] in the preoptic area (poa) of the rat hypothalamus. we ...19921292983
circadian periodicities of serum androgens, progesterone, gonadotropins and luteinizing hormone-releasing hormone in male rats: the effects of hypothalamic deafferentation, castration and adrenalectomy.serum testosterone (t), dihydrotestosterone (dht), progesterone (p), lh, fsh and luteinizing hormone-releasing hormone (lhrh) levels and the lhrh content in the medial basal hypothalamus (mbh) and preoptic area (poa) were estimated during a 24-h period. circadian rhythms, temporally unrelated to each other, were evident in serum fsh and lhrh and the mbh lhrh content; serum lh fluctuated randomly. in addition, serum t and dht demonstrated a parallel circadian pattern while serum t and p appeared ...1977338291
a daily neural signal for luteinizing hormone release in the untreated ovariectomized rat: changes in gonadotropin-releasing hormone content of the preoptic area and hypothalamus throughout the day.gonadotropin-releasing hormone (gnrh) content of preoptic areas (poa) and hypothalami, and serum gonadotropins of rats ovariectomized six weeks earlier were measured throughout the day in two experiments. in the first, rats were decapitated at 2 h intervals between 0800 and 1800 h. the entire preoptic-hypothalamic region was removed and extracted for radioimmunoassay (ria) of gnrh. serum gonadotropins measured by ria were highly variable but mean concentrations were not significantly different t ...1977322997
studies on an oncofetal antigen, poa.this paper describes the purification and partial characteristics of a putative oncofetal antigen, poa, which appears to be associated with the pancreas. poa is a glycoprotein of molecular weight between 800,000 and 900,000 daltons. it is found in fetal pancreas and pancreas cancer tissue, but not in normal adult pancreas. it is clearly different from carcinoembryonic antigen, other known tumor associated antigens, acute phase reactants and normal serum proteins. a quantitative rocket immunoelec ...1978101295
luteinizing hormone requirements for ovulation in the pentobarbital-treated proestrous rat.the lh requirements for ovulation in the pentobarbital-blocked proestrous cd rat have been studied by increasing serum gonadotropin levels through electrical stimulation of the brain and subsequently comparing the effects of timed hypophysectomy on ovulation and serum lh concentrations. the arcuate nucleus (arc) or the medial preoptic area (poa) was stimulated unilaterally for 45 min with matched pairs of biphasic rectangular pulses through a coaxial platinum electrode. serum lh was significantl ...1976987901
differential response of luteinizing hormone-releasing hormone in the basal hypothalamus and the preoptic area following anterior hypothalamic deafferentation and/or castration in male rats.serum lh, fsh and lhrh concentrations and the lhrh content in the medial basal hypothalamus (mbh) and the preoptic area (poa) were measured by radioimmunoassay in male rats 33 days after anterior hypothalamic deafferentation (ahd) and/or castration. in castrate rats following ahd, there was a significant decrease in serum lh, fsh, and lhrh concentrations, whereas, in intact rats, serum lh was elevated in ahd over the sham ahd rats. castration and ahd each caused a significant fall in the lhrh le ...1977318623
a rapid and simple micromethod to measure picograms of norepinephrine (ne) and dopamine (da) in small samples of brain tissue and pituitary gland.a rapid and simple procedure to determine dopamine (da) and norepinephrine (ne) in small tissue samples (mug quantities) is described. the radioenzymatic assay sensitivity, defined as twice the blank, is about 0.1 ng for ne and da. drugs known to modify brain catecholamine metabolism were shown to alter differentially da and ne concentration in the medial basal hypothalamus (mbh) of male rats. different areas of the brain and the pituitary gland, namely the parietal cortex, the pre-optic region ...1976993791
hypothalamic areas involved in prostaglandin (pg)-induced gonadotropin release. ii: effect of pge2 and pgf2alpha implants on follicle stimulating hormone release.the effect of unilateral intrahypothalamic implants of pge2 or pgf2alpha on fsh release in ovariectomized, estrogen-treated rats was studied. both pgs induced an equally small increase in plasma fsh following their implantation in the body of the arcuate nucleus-median eminence region (barh-me). levels were maximally elevated 120 min post-implantation. pge2 implanted in the caudal portion of the arh-me (tarh-post-me) also induced a similar increase in plasma fsh, whereas its placement in the reg ...1977870308
hypothalamic areas involved in prostaglandin (pg)-induced gonadotropin release. i: effects of pge2 and pgf2alpha implants on luteinizing hormone release.ovariectomized rats had a cannula inserted unilaterally within various hypothalamic areas. several days later they were primed with a sc dose of 10 microng of estradiol benzoate (eb). two days after priming they were etherized and an initial blood sample was drawn from the external jugular vein. an inner cannula containing pge2 or pgf2alpha at its tip was inserted into the previously implanted outer cannula. blood samples were drawn at 20, 40, 60, and 120 min following the implantation. pge2 ind ...1977870307
identification of aromatase in the reptilian brain.the present study tests the hypothesis that brain aromatase is an "ancient" property of nervous tissue and may be identified in homologues of the limbic system in a non-mammalian vertebrate, the turtle chrysemys picta. tissue homogenates (180 mg wet weight/2 ml) were incubated with [7 alpha-3h]androstenedione and cofactors for 60 min at 37 c. estrone (e1) was isolated and characterized by thin layer chromatography, methylation and recrystallization to constant specific activity. no estradiol-17 ...1977837883
the effect of noradrenaline, injected into the hypothalamus, on thermoregulation in the cat.1. noradrenaline (na) was microinjected into the anterior hypothalamic/preoptic area(ah/poa) of unanaesthetized cats held at ambient temperatures of 10, 22 or 35 degrees c. loci in which injection of na caused body temperature changes were also found to be sensitive to the febrile action of pge1. 2. at all ambient temperatures, na caused a dose-dependent fall in body temperature. however the mechanisms by which these temperature changes were brought about varied at different ambient temperatures ...1976994030
thermoregulation in the rabbit following intracranial injection of norepinephrine.the release of norepinephrine (ne) from nerve terminals in the anterior hypothalamic/preoptic area (ah/poa) of the rabbit may serve to raise body temperature. to further examine the putative neurotransmitter role of ne, bilateral microinjections of 5 or 10 mug ne were made into or near the ah/poa of 44 conscious rabbits exposed to an ambient temperature of 15 degrees c. microinjections into the ah/pos did not cause fever; they either had no influence on thermoregulation or rapidly induced ear va ...19751211462
autoradiographic localization of androgen-concentrating cells in the brain of the male domestic fowl.cells in the male fowl brain which accumulate radioactivity following 3h testosterone (t) administration were identified by autoradiography. labelled cells were found principally in hypothalamic, limbic and midbrain structures. marked uptake was observed in the preoptic area (poa) and in the anterior and posterior hypothalamus. there was also a significant amount of labelling in the archistriatum (arch), particularly in the nucleus taeniae (tn), and in the lateral septum. in the midbrain, substa ...1978683476
differential effects of brain lesions on thirst induced by the administration of angiotensin-ii to the preoptic region, subfornical organ and anterior third ventricle.(1) the possibility that water intake elicited by the administration of angiotensin-ii to the preoptic region (poa), subfornical organ and anterior third ventricle is mediated by separate neural systems was investigated in 58 male wistar rats using electrolytic lesion techniques. (2) lesions of the midlateral hypothalamus and paramedial rostral midbrain produced a significant reduction in water intake to angiotensin-ii microinjected into the poa but did not affect drinking following administrati ...19761276900
ontogeny of pancreatic oncofetal antigen.serum concentration of pancreatic oncofetal antigen (poa) was determined in human fetuses, newborns and pregnant women. the mean fetal concentration of poa (mean = 5.27 micrograms/ml) changed very little with gestational age. also, only a weak correlation was found between poa concentration of newborns (mean = 5.15 micrograms/ml) and their birth weight. it appears that between the 19th and 40th weeks of gestation poa exhibits no fetospecific features, i.e. poa concentration did not exceed signif ...19921290030
induction by nerve growth factor (ngf) of ngf receptor-like immunoreactivity in the preoptic area and hypothalamus of neonatal rats.nerve growth factor (ngf) was injected in the brain of neonatal rats. in eleven of thirty-one rats that received 1 microgram of mouse ngf (2.5s form) on postnatal day 3, ngf receptor-like immunoreactivity was found in the preoptic area (poa) and hypothalamus until 12 days after birth. however, no immunoreactivity was seen in the region of rats in the same group examined on day 20 or 45 and of uninjected control rats on days 1-45. these results indicate that ngf induces the transient appearance o ...19921376870
mapping of antibody binding epitopes of a recombinant poa p ix allergen.antibody binding epitopes of a recombinant poa p ix allergen were delineated using recombinant dna and solid-phase peptide synthesis procedures. the full-length cdna clone kbg60 and its four overlapping recombinant fragments, kbg60.1, kbg60.2, kbg8.3 and kbg10 which spanned the entire molecule were synthesized in e. coli with aid of the plasmid expression vector, pwr590.1. the antigenic and allergenic sites of these recombinant proteins were analyzed by elisa using human ige and murine igg antib ...19921383697
numerical taxonomy of some yellow-pigmented bacteria isolated from plants.phenetic data on over 60 heterotrophic, gram-negative, yellow chromogenic bacteria from plant material were collected and analysed using numerical taxonomic methods. marker strains representing 42 taxa were included in the analyses. at similarity levels of 80% or above, eight distinct clusters were obtained, the first four of which included yellow chromogens. custer i contained isolates from green healthy leaves of agrostis tenuis, festuca rubra, holcus lanata, lolium perenne and poa pratensis, ...19761011010
rast, skin and nasal tests and the history in grass pollen allergy.a comparison of the rast (phadebas), skin prick test, nasal test and a history of hay fever was made in 141 subjects, eighty-seven being prick test positive, with three concentrations of extracts of sweet vernal (anthoxanthum odoratum), cocksfoot (dactylis glomerata), meadow fescue (festuca elatior), rye (lolium perenne), timothy (phleum pratense), meadow (poa pratensis). in adequate concentration any of the species extracts would have sufficed for skin tests, with cocksfoot pollen the most pote ...19751053442
prolactin release induced by electrical stimulation of the hypothalamic preoptic area in unanesthetized sheep.the hypothalamic preoptic area (poa) was electrically stimulated through permanently implanted electrodes in 4 unanesthetized sheep. initiation of poa stimulation was followed witin 10-20 min by large increases in plasma levels of prolactin (prl). the stimulation-induced discharges of prl were consistently observed in both untreated and estradiol-treated castrated animals using 0.1 to 0.7 ma of applied current. since behavioral modifications were only sometimes associated with electrical stimula ...19751143630
il-4 and ifn (alpha and gamma) exert opposite regulatory effects on the development of cytolytic potential by th1 or th2 human t cell clones.the cytolytic potential of a total number of 118 cd4+ human t cell clones specific for purified protein derivative (ppd) from mycobacterium tuberculosis, tetanus toxoid, lolium perenne group i allergen (lol p i), poa pratensis group ix allergen (poa p ix), or toxocara canis excretory/secretory antigen(s) (tes) was assessed by both a lectin (pha)-dependent and a mhc-restricted lytic assay and compared with their profile of cytokine secretion. the majority of clones with th1 or th0 cytokine profil ...19921401925
effects of placing micro-implants of melatonin in the mediobasal hypothalamus and preoptic area on the secretion of prolactin and beta-endorphin in a previous study, we showed that the local administration of melatonin in the mediobasal hypothalamus (mbh), but not the preoptic area (poa), caused a premature increase in the secretion of fsh and growth of the testes in sexually inactive soay rams exposed to long days. to extend these observations, we have now measured blood concentrations of prolactin and beta-endorphin and the associated peripheral responses in the same animals, to establish whether the treatments produced multiple endocr ...19921402551
expression and thrombin cleavage of poa p ix recombinant allergens fused to glutathione s-transferase.the high-level expression and purification of poa p ix recombinant grass pollen allergens were examined utilizing a modified pgex plasmid, designated as pgex 2t-1. this vector permits frame-1 ligation of lambda gt11 cdna inserts and cleavage of the recombinant allergenic protein from the fusion partner glutathione s-transferase. the expression of the fusion proteins in water-soluble form varied among the transformants of the same bacterial strain and also between different host strains. purifica ...19921422262
expression of fos-like proteins in gonadotropin-releasing hormone neurons of syrian hamsters: effects of estrous cycles and metabolic female mammals, reproduction is sensitive to the availability of metabolic fuels, and food deprivation has been shown to suppress pulsatile lh secretion, attenuate the preovulatory lh surge, and prevent ovulation. it has been suggested that food deprivation impairs fertility by reducing the secretion of gnrh by gnrh-producing neurons in the forebrain. a series of experiments tested this hypothesis by examining the effects of estrous cycles and manipulations of metabolic fuel availability on t ...19921425420
effects of hyperthermia and stimulation of the hypothalamus on the activity of the phrenic nerve in hypo- normo- and hypercapnic rabbits.experiments were carried out on male rabbits, anesthetized with urethane, bilaterally vagotomized, paralysed and artificially ventilated. the preoptic area (poa) was stimulated at three different levels of co2: in hypo- normo- and hypercapnia under normothermia, moderate hyperthermia and hyperthermia. changes in central respiratory activity (monitored by phrenic nerve activity) due to co2 levels, stimulation of the poa during normothermia and progressively increased body temperature were investi ...19751163305
purification and partial characterization of the apoa-i of rabbit high density lipoprotein.purification of apoa-i from rabbit high density lipoproteins (hdl) gave one single band in sodium dodecylsulphate-polyacrylamide disc electrophoresis and reacted only with antiserum to apoa-i. the molecular weight was about 25000. the amino acid composition of rabbit ,poa-i gave a difference index of 7.4 compared to human apoa-i and of 6.5 compared to dog apoa-i. of the three carboxy terminal amino acid residues the rabbit protein has one in common with the dog. the amino acid sequence of twenty ...1978205614
female lordosis pattern in the male rat induced by estrogen and progesterone: effect of interruption of the dorsal inputs to the preoptic area and hypothalamus.lordosis behavior was very rare in castrated male rats which had been pretreated with 50 mug estradiol benzoate (eb) for successive 2 days and 1 mg progesterone (p) 6-8 hr prior to testing on the third day. only one out of 8 rats displayed lordosis in response to mounts by the sexually matured males. however, the occurrence of lordosis behavior was markedly increased in similarly treated castrated males in which the dorsal afferents to the preoptic area (poa) and hypothalamus were removed by the ...19751175525
blockade of testosterone-induced mounting behavior in the male rat with intracranial application of the aromatization inhibitor, androst-1,4,6,-triene-3,17-dione.propylene glycol (glycol) solutions containing either testosterone (t) or estradiol (e2) were infused directly into the preoptic area (poa) of longterm castrated rats in order to reinstate male copulatory behavior. in addition, castrated males were administered t or e2 in the poa in combination with a steroid that has been shown to block the aromatization of testosterone to estradiol, androst-1,4,6-triene-3,17-dione (atd). the facilitatory action of testosterone on mounting behavior was blocked ...19751204576
hypertrophy of gonadotropin releasing hormone-containing neurons after castration in the teleost, haplochromis the african cichlid fish, haplochromis burtoni, males are either territorial or nonterritorial. territorial males suppress reproductive function in the nonterritorial males, and have larger gonads and larger gonadotropin-releasing hormone- (gnrh) containing neurons in the preoptic area (poa). we describe an experiment designed to establish the causal relationship between large gnrh neurons and large testes in these males by determining the feedback effects of gonadal sex steroids on the gnrh ...19921460466
gabaergic influence on the development of the sexually dimorphic nucleus of male and female rats.a large number of estrogen-sensitive neurons in rat hypothalamus use gamma-aminobutyric acid (gaba) as a neurotransmitter. as estrogens influence the size of the sexually dimorphic nucleus (sdn) of the preoptic area it was tested whether perinatal treatment of rats with the gaba-agonistic drug muscimol can induce similar changes as estrogens. male and female rats were treated perinatally with muscimol or with the vehicle only and the vols. of the sdn of the preoptic area were determined morphome ...19921324079
dopaminergic regulation of luteinizing hormone-releasing hormone release at the median eminence level: immunocytochemical and physiological evidence in hens.theoretically, the most effective inhibitory control of hypophysiotropic luteinizing hormone-releasing hormone (lhrh) release might occur through a presynaptic inhibition of lhrh neuronal terminals at the median eminence (me) level. since: (a) we have recently reported the existence of synaptic contacts between dopamine- and lhrh-containing processes in the ewe me, and (b) nutritional deprivation induces an ovulatory failure in both birds and mammals, we have assessed the possibility that the an ...19921354335
temporal effects of fornix transection on brain tryptophan hydroxylase activity and plasma corticosterone levels.the effect of fornix transection on plasma corticosterone and on midbrain (mid), septum/preoptic (s/poa) or hippocampal (hip) tryptophan hydroxylase activity (tha) was studied in adult male rats. a mild stress resulted in higher levels of plasma corticosterone in operated as compared to sham-operated rats 6 and 40 h post-transection; however, at 30 days post-operation no difference was found. the response of tha to fornix transection was region-specific. no significant change in the s/poa region ...19761021715
aging changes in the beta-endorphin neuronal system in the preoptic area of the c57bl/6j mouse: ultrastructural hypothalami of aging rodents, beta-endorphin (beta-ep) neuron number and content are reduced. the objectives of this study were: first, to analyze ultrastructurally the population of neuronal elements in a selected region of the preoptic area (poa) in young and old mice; second, to study the beta-ep neuronal system in the same region to determine whether or not this population remains stable with age. vibratome sections from the most caudal poa through the diagonal band of broca were examined ...19921491742
localisation of aromatase activity in androgen target areas of the mouse brain.oestrogens are formed from androgens in the mouse brain, but the localization of aromatase activity is unresolved. immunocytochemistry has not detected aromatase in expected key androgen target areas such as the medial preoptic area. using a micropunch method and a sensitive in vitro 3h2o product detection assay, we report significant aromatase activity in adult male preoptic area (poa) and amygdala with [1 beta-3h]testosterone as substrate (vmax < or = 1,200 fmol 3h2o formed/mg protein/h), in c ...19921491788
tremorgenic mycotoxins produced by strains of penicillium spp. isolated from toxic poa huecu parodi.seventeen strains of penicillium spp. have been isolated from poa huecu parodi from the zapala zone, exhibiting toxicity to sheet. the following strains have been identified: p. crustosum, cyclopium, notatum, palitans, puberulum, verrucosum, viridicatum and penicillium spp. the toxigenic capacity of the strains was studied after growing them under suitable conditions. toxins produced were analysed by thin layer chromatography (tlc). penitrem a (pa) and penitrem b (pb) neurotoxins were identified ...19921494361
in vivo nuclear 3h-estradiol binding in brain areas of the rat: reduction by endogenous and exogenous vivo specific nuclear binding of [2, 4, 6, 7 (n)-3h]estradiol (3h-e2) as indicated by diethylstilbestrol (des)-blockable radioactivity, was measured 1 h after injection in adult intact male, untreated and testosterone propionate (tp)-pretreated or 5alpha-dihydrotestosterone (dht)-pretreated gonadectomized (gdx) male and female rats. there was no sex difference in specific 3h-e2 binding in brain areas and anterior pituitary (pit) of untreated gdx animals. dht pretreatment had no effect on bind ...19761021716
progesterone promotes rapid desensitization of alpha 1-adrenergic receptor augmentation of camp formation in rat hypothalamic slices.we previously demonstrated that norepinephrine (ne) induction of camp accumulation in slices of the preoptic area (poa) and middle hypothalamus (mh) is reduced by in vivo administration of progesterone to estradiol-primed rats, apparently by eliminating alpha 1-receptor augmentation of beta-receptor-stimulated camp formation. the present studies examined whether in vitro exposure to progesterone would also depress ne-stimulated camp synthesis. poa and mh slices from estradiol-primed females were ...19921319002
effects of temperature and neuroactive substances on hypothalamic neurones in vitro: possible implications for the induction of fever.this paper reviews some of our findings which have shown the usefulness of in vitro methods in the study of hypothalamic neurones. (1) membrane current analyses of dispersed neurones of the rat preoptic and anterior hypothalamus (poa) during thermal stimulation have revealed that warm-sensitive neurones are endowed with a non-inactivating na+ channel having a high q10 in the hyperthermic range (35-41 degrees c). (2) a brain slice study has shown that neurones in the organum vasculosum lamina ter ...19921319197
expression of the cell surface antigen detected by the monoclonal antibody a7 in pancreatic carcinoma cell a previous study, we used a murine monoclonal antibody, a7, against human colon carcinoma as a drug-carrier to treat colorectal cancer. in the present study, we found that mab a7 also reacted immunohistochemically with 73% of human pancreatic carcinoma cell lines, with the a7 antigen mainly being detected on the cell surface. however, the a7 antigen was found in only 9% of the spent media of these human pancreatic carcinoma cell lines by elisa. on the other hand, the positive incidence of ca1 ...19921327320
localization of luteinizing hormone-releasing hormone in the preoptic area and hypothalamus of the rat using determine the localization of luteinizing hormone-releasing hormone (lhrh), five brains from adult male rats were serially sectioned in a cryostat at - 10 c in either the frontal, horizontal or sagittal planes. acetic acid-ethanol extracts of each section were assayed for lhrh using radioimmunoassay (ria) and in some cases using bioassay as well. approximately 0.2 ng lhrh was concentrated in medial basal preoptic (mb-po) tissue overlying the rostral portion of the optic chiasm. this lhrh appe ...19751095362
bombesin-induced hypothermia and hypophagia are associated with plasma metabolic fuel alterations in the rat.microinfusion of bombesin into the preoptic area (poa) has previously been shown to reduce core body temperature and feeding in rats that are food-deprived or made hypoglycemic with insulin. the present study determined the metabolic fuel state of rats under these experimental conditions. in addition, changes in plasma metabolic fuels following the microinfusion of bombesin (50 ng/0.25 microliters) into the poa were evaluated. rats (n = 8) were tested under conditions of food satiation, food dep ...19921319589
further studies on central actions of nitroglycerin and lack of evidence for nitroglycerin interacting on [3h]clonidine binding sites in cortex membranes.decerebration and transection of the spinal cord totally abolished the hypotensive and tachycardiac responses to i.c.v injection of nitroglycerin (ntg) and reduced the tachycardia induced by i.v. injection of the drug. the hypotensive responses to i.v. injection of sodium nitroprusside were not altered by decerebration. microinjection of ntg (0.1-1.0 nmol) into anterior hypothalamic medial preoptic area (ah/poa) produced dose-dependent decreases in mean arterial pressure and heart rate, but mini ...19921318374
estradiol selectively regulates alpha 1b-noradrenergic receptors in the hypothalamus and preoptic area.we previously demonstrated that estradiol administered in vivo elevates the number of alpha 1-adrenoceptors in preoptic area (poa) and hypothalamic membranes from ovariectomized female rats and potentiates alpha 1 receptor augmentation of beta-adrenoceptor-stimulated camp formation in slices from these brain regions. present studies examined (1) if estradiol selectively regulates any alpha 1-adrenoceptor subtype, and (2) which alpha 1 receptor subtype mediates the augmentation of camp synthesis. ...19921328561
in vitro autoradiographical localization of melatonin binding sites in the caprine brain.the recent development of a specific 2-[125i]-iodo-melatonin ligand has led to the identification of 125i-melatonin binding sites in the brains of numerous mammalian species. the present study reports the localization of 125i-melatonin binding sites in the brain of the dairy goat. six previously untreated female goats, aged 5-7 years, were culled under natural light between 0900 and 1100. brains and pituitaries were immediately dissected out and frozen on dry ice. both transverse and sagittal se ...19921331395
neuroendocrine responses to social regulation of puberty in the female house mouse.first estrus is advanced in female house mice exposed to an adult male and delayed in those housed in groups. experiments were conducted to explore possible mechanisms by which the hypothalamus integrates these puberty-regulating social signals. female mice weaned at 21 days of age were placed in groups of 8 (g8jf), a juvenile female with a juvenile male (jfjm) or juvenile female with an adult male (jfam). all females were ovariectomized on day 28 and sacrificed on day 29. there was no significa ...19921565209
role of the ovlt in the febrile response to circulating pyrogens.the available data suggest that circulating endogenous pyrogens (eps) probably do not penetrate the brain, but interact with sensory elements in the organum vasculosum laminae terminalis (ovlt) which may involve 5ht and sp as neurotransmitters. it is proposed that substance p (sp) may affect thermo-regulatory neurons in the preoptic area (poa) directly or induce the local synthesis of cytokines that secondarily act on these neurons. recent evidence indicates that endothelial cells in the ovlt bi ...19921384084
systemic injection of tnf-alpha attenuates fever due to il-1 beta and lps in rats.the effect of tumor necrosis factor-alpha (tnf-alpha) on the febrile response to interleukin-1 beta (il-1 beta) was investigated in rats. while both of these substances are capable of causing fever when injected into rats, an earlier study showed that the injection of antiserum against tnf-alpha enhanced endotoxin [lipopolysaccharide (lps)] fever, suggesting that physiological levels of circulating tnf may act to limit the magnitude of fever. in the present study, the intraperitoneal injection o ...19921443236
interaction between ovarian and adrenal steroids in the regulation of gonadotropin secretion.recent work from our laboratory suggests that a complex interaction exists between ovarian and adrenal steroids in the regulation of preovulatory gonadotropin secretion. ovarian estradiol serves to set the neutral trigger for the preovulatory gonadotropin surge, while progesterone from both the adrenal and the ovary serves to (1) initiate, (2) synchronize, (3) potentiate and (4) limit the preovulatory lh surge to a single day. administration of ru486 or the progesterone synthesis inhibitor, tril ...19921562521
bombesin-induced hypothermia: a dose-response and receptor antagonist study.bombesin infusion into the preoptic area (poa) has previously been shown to induce hypothermia in rats that are food deprived or made hypoglycemic with insulin. the present study evaluated the potency and receptor specificity of this response. bombesin was microinfused into the poa of food-deprived rats (n = 7) and insulin-pretreated rats (n = 7) at doses of 0, 5, 12, 25, and 50 ng/0.5 microliters. changes in core body temperature (rectal) were assessed at 1 h. hypothermia was observed under bot ...19921333086
brain aromatase cytochrome p-450 messenger rna levels and enzyme activity during prenatal and perinatal development in the rat.aromatase cytochrome p-450 (p-450arom) enzyme activity catalyzes the conversion of androgens to estrogens in specific brain areas. during development local estrogen formation is thought to influence the sexual differentiation of neural structures (i.e. increase neurite growth and establish neural circuitry) and modulate reproductive functions. this study was undertaken to investigate the ontogeny of the (p-450arom) enzyme and its messenger rna (mrna) in medial basal hypothalamic (mbh) and preopt ...19921337928
the human hypothalamus: comparative morphometry and photoperiodic influences.the concept of the hypothalamus as a distinct neurological entity concerned with a variety of regulatory processes dates back to the end of the 19th century. before 1900 there were only vague intimations of the function of the brain surrounding the third ventricle and these were based primarily on various pathological and assorted clinical observations. since then a large body of evidence has been derived implicating that the hypothalamus contains the control systems which are critically involve ...19921480746
induction of ige antibodies in mice with recombinant grass pollen this study, recombinant poa pratensis (poa p) ix allergens were examined for their in vivo allergenicity and antigenicity. immunization of mice with a fusion protein (fp) comprising beta-galactosidase and recombinant kbg8.3 (rkbg8.3) allergen induced high titres of both igg and ige antibodies. by contrast, immunization with rkbg60.2, which represents the n-terminal fragment of rkbg8.3, induced only igg antibodies. the ige antibody titre specific to kentucky bluegrass (kbg) was significantly h ...19921628894
pharmacological and mechanical heterogeneity of cat isolated ophthalmociliary artery.the mechanical, histological and pharmacological properties of the isolated cat ophthalmociliary artery are reported and compared for passively stretched ring segments from three locations on the artery. ring segments were mounted in a modified myograph system after the method of hogestatt, andersson and edvinsson (1983, acta physiol scand. 117, 49-61) and comparative length tension curves were measured. the most distal segment (doa), nearest the eye, developed by far the smallest maximal tensio ...19921355740
immunocytochemical localization of beta endorphin and gonadal steroid regulation of proopiomelanocortin messenger ribonucleic acid in the the ewe, estradiol and progesterone inhibit luteinizing hormone (lh) secretion during the breeding season. endogenous opioid peptides (eop) are also inhibitory to lh secretion, and both estrogen and progesterone have been reported to enhance eop inhibition of lh release. which eop are involved in this inhibition is unclear. in this study, we concentrated on beta-endorphin because evidence for its ability to inhibit lh secretion exists in ewes. we first studied the distribution of beta-endorph ...19921369589
segregated thalamocortical pathways to inferior parietal and inferotemporal cortex in macaque monkey.inferior parietal and inferotemporal cortex, which process different aspects of visual information through largely segregated pathways from the visual cortex, both receive thalamic afferents from the pulvinar complex. we examined the topography of pulvinar projections to these two cortical regions by placing multiple injections of different tracers (fluorescent dyes, horseradish peroxidase) in the inferotemporal and inferior parietal cortex of macaque monkeys. the patterns of label observed afte ...19921375095
proligodendroblast antigen (poa), a developmental antigen expressed by a007/o4-positive oligodendrocyte progenitors prior to the appearance of sulfatide and galactocerebroside.evidence is presented for the immunological identification of a developmental antigen appearing at a critical point in the oligodendroglial lineage. specifically, monoclonal antibody a007 recognizes cells in the oligodendrocyte lineage at two distinct stages. analyses of purified lipid standards and lipid extracts from galactocerebroside-positive (galc+) oligodendrocytes by enzyme-linked immunosorbent assay, lipid dot blot, and immuno-tlc demonstrated that a007 recognizes sulfatide (sul) and sem ...19921573402
role of 5-hydroxytryptamine receptors on luteinizing-hormone-releasing hormone release in the ovariectomized, estradiol-treated rat.the present experiments examined the effect of ketanserin [5-hydroxytryptamine-2 (5-ht2) antagonist] and 8-hydroxy-2-(di-n-propylamino) tetralin (8-oh-dpat) (5-ht1 agonist) on the in vitro release of luteinizing-hormone-releasing hormone (lhrh) from the medial basal hypothalamus-preoptic area-suprachiasmatic nucleus region (mbh-poa-scn) of ovariectomized (ovx), estradiol-(e2) treated rats using in vitro superfusion techniques. regularly cycling female holtzman rats (250-300 g) were maintained on ...19921386277
characterization and mapping of melatonin receptors in the brain of three mammalian species: rabbit, horse and sheep. a comparative in vitro binding study.melatonin receptors were characterized in the brains of three mammals (rabbit, horse and sheep) by an in vitro binding technique, using 2-[125i]iodomelatonin as labelled ligand. although binding sites for melatonin have been described recently in several vertebrate species (including the sheep), the rabbit and the horse have not been the subject of investigation so far. apart from characterization, the present report describes receptor distribution in a number of brain regions, thus allowing for ...19911645852
hypothalamic neuronal responses to interleukin-6 in tissue slices: effects of indomethacin and naloxone.we recently reported that human recombinant interleukin-6 (hril-6) microinjected into the preoptic area (poa) of guinea pigs induced fever at high doses, suggesting that il-6 may be another endogenous pyrogen. this study was undertaken to determine whether hril-6 affects the single-unit activity of thermosensitive and thermally insensitive neurons in hypothalamic tissue slices and whether indomethacin (indo) or naloxone (nal), a cyclooxygenase inhibitor and a mu-opioid receptor antagonist, respe ...19921504850
aromatase as a cellular marker of testosterone action in the preoptic area.we recently showed, using a new immunocytochemical technique, that aromatase-immunoreactive neurons are a specific marker for the sexually dimorphic medial preoptic nucleus (pom) in quail and that the number of these immunoreactive cells is markedly increased by a systemic treatment with testosterone (t). since the pom is a key site for the activation of copulatory behavior by t and this androgen must be converted into estrogen by local aromatization within the pom before it can exert its behavi ...19921557450
effects of estrous cycle, estrogen and progesterone administration on the antidromic and orthodromic reaction threshold of medial preoptic neurons in the rat the present study, attempts were made to evaluate the effects of the estrous cycle and the administration of estradiol (ovx-e) or progesterone (ovx-p) after ovariectomy on the threshold of antidromic (ad) and orthodromic (od) responses of neurons in the medial preoptic area (poa) induced by electrical stimulation of the median eminence-arcuate nucleus (arc) of the hypothalamus. single units were evaluated with extracellular recording. the threshold of ad and od response in poa neurons decline ...19921391184
preoptic-brainstem connections and maternal behavior in rats.this study presents evidence supporting the view that preoptic area (poa) projections through the ventral tegmental area (vta) to lower brainstem regions are important for maternal behavior in postpartum rats. experiment 1 demonstrated that bilateral coronal knife cuts posterior to the vta disrupted maternal behavior, and experiment 2 demonstrated a similar disruption when a unilateral knife cut that severed the lateral connections of the medial poa was paired with a contralateral knife cut post ...19911663755
purification and characterization of an allergen from celery immunochemically related to an allergen present in several other plant species. identification as a profilin.the purification of a 15 kd allergen from celery was obtained by a four step procedure. evidence for at least two isoallergenic forms was obtained after analysis by two-dimensional-electrophoresis. a rabbit polyclonal antibody raised against this purified allergen allowed us to confirm our precedent results on the occurrence of allergenically and molecular mass-related components in celery and birch and mugwort pollens. in addition such components were also present in numerous other species like ...19921525697
anogenital distance at birth as a predictor of volume of the sexually dimorphic nucleus of the preoptic area of the hypothalamus and pituitary responsiveness in castrated adult rats.variation in anogenital distance (agd) in female newborn rats depends upon androgenization secondary to transplacental/transmembraneous testosterone from adjacent intrauterine male siblings. since the size of the sexually dimorphic nucleus of the preoptic area of the hypothalamus (sdn-poa) and the degree of pituitary sensitivity to gnrh are neuroendocrine markers of neonatal androgenization, we compared these to agd in castrated adult male and female rats. compared to 1-day-old female rats with ...19921547306
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