摘要:

Three control point enzymes of the Embden-Meyerhof pathway, hexokinase (HK), phosphofructokinase (PFK) and pyruvate kinase (PK) were measured by quantitative histochemical methods in individual hypothalamic nuclei of adult neonatally androgenized female rats. HK activity was significantly increased in anterior hypothalamic nuclei: medial preoptic, lateral preoptic, and suprachiasmatic. PK was significantly elevated in the lateral preoptic and suprachiasmatic nuclei of the anterior hypothalamus and also in the medial mamillary nucleus and median eminence. No significant changes occurred in PFK activity.

ISSN:0028-3835    

DOI:10.1159/000122715

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Using quantitative microfluorimetry in combination with tyrosine hydroxylase (TH) inhibition (α-methyltyrosine-p-methylester; H 44/68), the effect of pregnant mare’s serum gonadotropin (PMS, 10 IU day 30) on the levels and turnover of catecholamine (CA) in the subependymal layer (SEL), the medial (MPZ) and lateral palisade zone (LPZ) of the median eminence (ME) was studied on days 30, 31, 32 and 33 of life in the female rat. Serum LH concentrations were studied by radioimmunoassay. LH concentrations reached maximal levels between 18.00–20.00 on day 32. During 15.00–17.00 in the critical period of day 32 the reticulo-hypothalamic noradrenaline (NA) turnover was dramatically increased in SEL compared to other times during day 32 and the same time on day 33 and day 30, whereas the dopamine (DA) levels in the LPZ were increased and the DA turnover decreased in this region when compared with PMS-treated rats studied on day 31 during 15.00–17.00. A partial increase of NA turnover in SEL was already seen in the afternoon of day 31 compared with PMS-treated rats studied one day earlier. Also NA turnover in the medial preoptic area (MPOA) and DA turnover in the olfactory tubercle (TO) were increased and decreased respectively during the critical period in the afternoon of day 32 compared with PMS-treated rats studied in the morning of the same day, whereas such comparisons did not reveal any difference in DA turnover in the parts of the nuc. caudatus (CAUD) and nuc. accumbens (ACQ studied and in NA turnover in nuc. interstitialis striae terminalis, ventral part (NISTV). The present findings give support for the view that an inhibitory DA and a facilitory NA mechanism exist in the control of PMS-induced ovulation. It is suggested that this control may partly be exerted via NA terminals in MPOA (and possibly in SEL) and via DA terminal

ISSN:0028-3835    

DOI:10.1159/000122716

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Pregnant mare’s serum gonadotropin (PMS; 10 IU day 3O)-induced ovulation was used as a model to study the effect of drugs interfering with monoamine neurotransmission on CNS processes controlling ovulation. The drugs were administered during the critical period on day 32 and tubal eggs were counted in the morning of day 33. When injected during the critical period, dopamine (DA) receptor agonists such as apomorphine, ET 495, ergotamine, 2-bromo-α-ergocryptine, lergotrile and ergocornine inhibited ovulation, an effect which was counteracted by the DA receptor blocking agent, pimozide. However, by itself pimozide had no significant effect, whereas combined noradrenahne (NA) and DA receptor blocking agents such as chlorpromazine and clozapine inhibited ovulation. α- and β-adrenergic blocking agents and drugs influencing 5-hydroxytryptamine (5-HT) neurotransmission did not affect ovulation. LH-RH removed the ovulatory blockade induced by ET 495 in the same dose-range as it removed pentobarbital-induced blockade of ovulation. Furthermore, ergocornine did not block ovulation after the critical period and was less effective when given prior to the critical period. Therefore it is likely that the DA receptor agonists act via a central action. Thus, the present findings give further support for the existence of a central inhibitory DA and facilitory NA mechanism in the control of PMS-induced ovulation in the immature female

ISSN:0028-3835    

DOI:10.1159/000122717

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

The lordosis response of 27 ovariectomized senile female rats (20 to 32 months old) primed with either estrogen-progestrone (E/P) or estrogen (E) alone was studied and compared with that of ovariectomized young adult rats (3 to 5 months old). As compared with the young rats, out of the 27 senile rats, only 11 showed decreased response with E/P priming and 6 with E priming only. When senile rats are classified into 4 groups according to their vaginal smear pictures and ovarian findings, i.e., prolonged vaginal cornification (PVC) with polyfollicular ovaries, anestrus (ANE) with atrophic ovaries, prolonged diestrus with hyperluteinized ovaries, and still preserved cycle, there is no significant difference in the incidence of decreased lordosis response among groups. In the 11 senile rats showing decreased response, the responsiveness of the system for sexual behavior to P seems to be decreased in 5 rats without changes in the responsiveness to E and that to E decreased in 6 rats. The lordosis response did not improve after adaptation in the rats which showed decreased response. The dysfunction of gonadotropin (Gn) secretion in senile female rats seems to occur earlier than aging of the system for behavioral estrus.

ISSN:0028-3835    

DOI:10.1159/000122718

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Normal, castrate and estradiol benzoate (EB; 1 µg/100 g b.w. × 6d, s.c.)-treated castrate male rats were utilized to study the short term effects of these treatments upon the incorporation of 3H-glycine into LH-RH in vitro. The rise in serum LH and FSH observed in the untreated castrates was prevented by EB therapy. The treatments had no significant effect upon serum LH-RH levels or the incorporation of 3H-gly into LH-RH. EB treatment markedly (p < 0.01) increased the hypothalamic LH-RH concentration and significantly lowered the specific activity (nCi/ng) of the 3H-gly-LH-RH (p < 0.05). These results suggest that EB acts both on the pituitary and hypothalamus to suppress gonadotropin (Gn) release, but that, at the time period studied, neither castration or EB-treatment had any apparent effect upon hypothalamic LH-RH synthesi

ISSN:0028-3835    

DOI:10.1159/000122719

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Pineal nuclear receptor estradiol complex determined by the 3H-estradiol exchange assay exhibited a kd = 0.42 nisi. Its concentration was maximal at proestrus and after administering 2–20 µg of estradiol to spayed rats. It was also detected in 6-day-old rats, before full maturation of pineal sympathetic nerves is attained. Superior cervical ganglionectomy caused nuclear receptor estrogen complexes (NREC) to decrease by 48 and 65% 5 and 14 days later; estradiol administration brought about increases of complex levels (1.9–2.3-fold) which were significantly smaller than in control or decentralized rats (3.4–3.9-fold). The time course of accumulation and retention of nuclear complexes was not affected by ganglionectomy. Isoproterenol restored the basal levels of NREC, but inhibited the effects of estradiol on complex accumulation; propranolol, administered simultaneously with estradiol also inhibited estrogen effects on the pineal. Estradiol incubation in vitro increased pineal nuclear receptor hormone levels and enhanced the conversion of serotonin into melatonin and 5-methoxytryptophol; no changes in hydroxy-indole-O-methyl transferase (HIOMT) activity were detected. These data support the conclusion that accumulation and retention of pineal NREC are under partial dependence upon sympathetic

ISSN:0028-3835    

DOI:10.1159/000122720

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Ten patients with isolated growth hormone (GH) deficiency and 13 age-matched normal controls were studied. All patients were below the 3rd percentile in height and weight. All but 1 subject were studied for 3 or 4 consecutive nights in the sleep laboratory which included monitoring of the EEG, EOG, EMG, and EKG. GH samples were taken during sleep in 6 of the 10 patients. There were no significant differences in the slow-wave sleep (SWS) parameter between the 2 groups, nor was there any difference when all growth hormone patients were compared to controls. The age group comparisons for the percent of rapid eye movement (REM) sleep parameter revealed a significant difference between GH and controls for the youngest group only (p<0.05). Similar results were obtained when the GH subjects were grouped according to bone age. A significant decline in SWS was found with increasing chronological age (p < 0.02), while the REM parameter did not show any significant changes across age categories. None of the patients showed a sleep-related peak in GH secretion. These data are not compatible with the hypothesis of a monotonic relationship between SWS and GH secretion.

ISSN:0028-3835    

DOI:10.1159/000122721

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Prostaglandin E2 (PGE2), PGF2α, or PGF2β was infused into a lateral ventricle of the brain of adult male rats, after pretreatment with normal rabbit serum (NRS) or anti-LH-RH serum, and the concentration of LH in arterial plasma was determined. I.v. administration of anti-LH-RH serum 2.5 min prior to the infusion of 2 µg or 20 µg of PGE2 significantly inhibited the PGE2-induced rise of plasma LH. Intraventricular infusion of 20 µg of PGF2αor PGF2β into NRS-pretreated animals caused a marked increase in the plasma LH concentration; whereas, prior i.v. administration of anti-LH-RH serum blocked the PG-induced rise in plasma LH levels. It is concluded that PGE2, PGF2α, and PGF2β stimulate the release of LH primarily by enhancing the release

ISSN:0028-3835    

DOI:10.1159/000122722

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Early in the history of studies on the release of ACTH by stress there were indications that ACTH might be released by multiple factors. But the neurohumoral theory, as formulated by G. W. Harris, suggested that every hypophysial hormone had its unique hypothalamic controlling agent and a search for the unique ACTH-releasing hormone went on for about 20 years. This review reexamines the case for multiple releasers of ACTH.

ISSN:0028-3835    

DOI:10.1159/000122723

出版商:S. Karger AG    

年代:1977

数据来源: Karger

ISSN:0028-3835    

DOI:10.1159/000122724

出版商:S. Karger AG    

年代:1977

数据来源: Karger