bluuebunny/crossref_metadata_2025_split huggingface dataset:
Growth hormone and prostatic tumours: localization using a monoclonal human growth hormone antibody
Authors: Sibley P. E. C , Harper M. E. , Peeling W. B. , Griffiths K. 
Published: December 2008

ABSTRACT
The immunocytochemical detection of endogenous human GH and the binding of exogenously applied human GH in tumour tissue from patients with benign prostatic hyperplasia or prostatic carcinoma is reported. Monoclonal human GH antibody binding was exclusively to the connective tissue in both benign and carcinomatous specimens. Specificity control experiments indicated that the antibody could be absorbed with human GH but not with human prolactin. Preincubating the sections with human GH considerably altered the immunocytochemical staining, reducing the reaction product within the connective tissue in a concentration-dependent manner and revealing a binding site for GH within the cytoplasm of epithelial cells.
J. Endocr. (1984) 103, 311–315
Studies on inhibin-like peptide in gastric juice and serum of patients with duodenal ulcers
Authors: Shanbhag S. A. , Sheth A. R. , Nanivadekar S. A. , Sheth N. A. 
Published: December 2008

ABSTRACT
Immunoreactive inhibin-like material (ILM) was measured by radioimmunoassay in serum and gastric juice samples of 23 fasting normal men and 23 men with duodenal ulcers (DU). Concentrations of ILM in gastric juice and serum of patients with DU were significantly higher than those in normal men (P <0·01). A strong positive correlation (r = 0·894) was observed between pH and ILM levels in gastric juice of normal men but not in patients with DU. Inhibin-like material in the gastric juice had a chromatographic profile similar to that of human seminal plasma.
J. Endocr. (1984) 103, 389–393
The oestrogenicity of equol in sheep
Authors: Kaziro R. , Kennedy J. P. , Cole E. R. , Southwell-Keely P. T. 
Published: December 2008

ABSTRACT
The effects of intramuscular injection of synthetic racemic equol (±3-(4-hydroxyphenyl)-3,4-dihydro2H-1-benzopyran-7-ol) into wethers have been examined with respect to maintenance of plasma level, teat growth rate and the activity of the respiratory enzyme glucose-6-phosphate dehydrogenase. At a dose rate of 1·03 mmol/day a steady rise in 'total' (free plus conjugated) equol in plasma occurred to 1·78μmol/l in 4 days. A dose rate of 2·07 mmol/day produced only a further slight increase in plasma equol. At a lower dose rate of 0·52 mmol/day the plasma concentration reached 0·62 μmol/l in 2 days and this was not exceeded thereafter. At the dose rate of 1·03 mmol/day over 7 days significant increases in teat length and glucose-6-phosphate dehydrogenase activity occurred but no significant changes were observed at the dose rate of 0·52 mmol/day. It appears that threshold levels of intake of equol which maintain a plasma level of about 1·65 μmol/l are needed for oestrogenic effects to become apparent within a relatively short time.
Administration of 1·03 mmol/day over 5 days to ovariectomized ewes produced significant increases in uterine weight equivalent to those produced by 92 nmol stilboestrol dipropionate. Thus stilboestrol was apparently 56000 times more potent than racemic equol.
J. Endocr. (1984) 103, 395–399
Calcitonin may modulate placental transfer of calcium in ewes
Authors: Barlet J.-P. 
Published: December 2008

ABSTRACT
In pregnant ewes bearing twin fetuses and fed an adequate Ca diet, the consequences of calcitonin (CT) deficiency (induced by thyroidectomy performed on day 30 of gestation, associated with daily thyroxine supplementation) differed according to the time of pregnancy. Such a deficiency had no significant effect either on fetal total body Ca content or on placental transfer of Ca in 77-day-old fetuses. On the contrary, CT deficiency for 110 days (on day 140 of pregnancy) was associated with an increased Ca concentration in fetal total body and increased placental transfer of Ca from the dam to its fetus, which did not occur in five thyroidectomized ewes supplemented with thyroxine and CT. This indicates that CT might protect the skeleton of the pregnant female against excessive demineralization by modulating placental transfer of Ca, when such a transfer becomes important, during periods of intense mineralization of the fetal skeleton.
J. Endocr. (1985) 104, 17–21
Mitogenic actions of insulin on fetal and neonatal rat cells in vitro
Authors: Crace C. J. , Hill D. J. , Milner R. D. G. 
Published: December 2008

ABSTRACT
Insulin has been implicated in the regulation of fetal growth. The aim of these studies was to determine if insulin has a direct mitogenic effect on fetal and neonatal rat cells in vitro. Myoblasts and fibroblasts were isolated from skeletal muscle and grown until myotube formation began or until fibroblasts were confluent. The cultures were then incubated in the presence of insulin (10−5–10−1 units/ml) and its effects were measured by the cellular incorporation of [3H]-thymidine. Myoblasts from fetuses of 21 days of gestation showed a marked, linear dose–response to insulin, significant increases over control values being observed at 2 × 10−5 units/ml or 2 × 10−4 units/ml in five out of seven experiments. Neither myoblasts from 19-day fetuses or neonates nor fibroblasts from animals of any of the three ages showed a significant thymidine uptake response to insulin. Myoblasts released immunoreactive somatomedin-C-like activity into the culture medium, but this was not related to fetal age nor to the presence of insulin in the culture medium. The results suggest that insulin may have a direct role in fetal muscle growth.
J. Endocr. (1985) 104, 63–68
Effects of dietary energy supply on serum thyroxine, tri-iodothyronine and insulin concentrations in young horses
Authors: Glade M. J. , Reimers T. J. 
Published: December 2008

ABSTRACT
The effects of meal ingestion on the circulating concentrations of the growth-regulating hormones thyroxine (T4), tri-iodothyronine (T3) and insulin were examined in weanling Thoroughbreds fed 70% (diet A), 100% (diet B) or 130% (diet C) of their energy and protein requirements. Peak insulin concentrations occurred 1, 2 and 3 h after the ingestion of diets C, B and A respectively. Increases in plasma glucose concentrations preceded the increases in serum insulin concentrations. Serum T4 concentrations increased after the ingestion of diets A and B and decreased after diet C. In contrast, serum T3 concentrations were unaffected by ingestion of diet A but increased after the ingestion of diets B and C. The increase was much greater and more rapid in the horses fed diet C. However, the decrease in T4 concentration was five times greater than the increase in T3 concentration. Accelerated insulin secretion after the ingestion of a meal high in energy (carbohydrate) content was therefore associated with decreased T4 secretion and accelerated T4 conversion to T3. However, 6 months later serum T4 and T3 concentrations were unaffected by meal ingestion.
J. Endocr. (1985) 104, 93–98
Rapid changes in growth hormone regulation and hypothalamic somatostatin after transection of anterolateral pathways to the medial-basal hypothalamus in the rat
Authors: Kakucska I. , Antal M. , Kárteszi M. , Makara G. B. 
Published: December 2008

ABSTRACT
Plasma and pituitary GH content, in-vitro GH release and somatostatin-like immunoreactivity (SLI) in the stalk-median eminence were studied up to 7 days after making an anterolateral cut (ALC) around the medial-basal hypothalamus. Plasma GH concentration increased within 15 min to a very high level, then fell to a high level which was unchanged for several hours. The GH concentration then steadily decreased between days 2 and 7. The SLI content in the stalk-median eminence decreased to 3·5% of the control value within 3 days. The GH content of the anterior pituitary gland was 58·8% of the control value by 1 week after the operation but the in-vitro sensitivity to somatostatin of the GH cells failed to change. Pentobarbitone injection stimulated GH release in the sham-operated controls but decreased it in the rats with an ALC.
These findings suggest that transection of somatostatin-containing fibres is followed by a rapid rise and a lasting high concentration of plasma GH which slowly returns towards lower levels in parallel with a marked depletion of pituitary GH content. In rats with transected somatostatin innervation of the median eminence, sodium pentobarbitone probably decreases GH secretion by depressing the secretion of GH-releasing hormone.
J. Endocr. (1985) 104, 121–127
Inhibition of growth hormone release by rumen distension in female goats
Authors: Tindal J. S. , Blake L. A. , Simmonds A. D. , Hart I. C. 
Published: December 2008

ABSTRACT
Six rumen-fistulated, overnight-fasted, female British Saanen goats were used. In preliminary experiments on two of the goats, evidence was obtained that inflation of a balloon with water in the cranial sac of the rumen was accompanied by inhibition of GH release. In a definitive series of experiments on the other four goats (one goat on 1 day = one experiment), a total of 96 experiments were carried out, 48 of which were balloon inflations with 2·5 litres water at 37 °C in the cranial sac of the rumen for 40 min and 48 were control experiments on alternate days. It was found that the mean plasma GH concentration of the samples taken at the end of the 40-min inflation period was significantly (P < 0·05) lower than the mean value of the samples taken at the start of inflation. Mean control values at the start and finish of inflation were not significantly different. There were no significant differences between mean plasma insulin concentrations at the start and finish of inflation in experimental and control groups. It is concluded that distension of the cranial rumen in the goat is a signal which can inhibit the release of GH.
J. Endocr. (1985) 104, 159–163
Influence of growth hormone, corticosterone, corticotrophin and changes in the environmental temperature on pituitary-ovarian function in the immature rat
Authors: Wilson C. A. , Buckingham J. C. , Morris I. D. 
Published: December 2008

ABSTRACT
The influence of various endocrine and environmental factors on pituitary-ovarian function was studied in peripubertal rats treated with pregnant mare serum gonadotrophin (PMSG). Pregnant mare serum gonadotrophin induced ovulation in rats aged 27 days provided they weighed over 60 g. The response was preceded by a marked hypersecretion of LH which was detectable by radioimmunological and biological assay methods. In contrast, smaller rats of the same age did not ovulate in response to PMSG apparently because of the secretion of a pleiomorphic form of LH which, although immunoreactive, appeared to be biologically inactive. Ovarian function, assessed by response to exogenous gonadotrophins and by measurement of 125I-labelled human chorionic gonadotrophin binding, was normal despite the presence of the biologically inactive pleiomorph. Exposure of the small PMSG-treated rats to a high environmental temperature (39 °C) or treatment with corticosterone or GH altered the nature of the LH in the blood so that it was active in both assay systems and facilitated ovulation as also did ACTH. The results suggest that the abrupt change in the nature of the LH released by the pituitary gland essential for the initiation of ovulation may be affected by GH, corticosterone or a raised environmental temperature.
J. Endocr. (1985) 104, 179–183
Acute and chronic effects of a gonadotrophin-releasing hormone antagonist on pituitary and testicular function in monkeys
Authors: Akhtar F. Bint , Weinbauer G. F. , Nieschlag E. 
Published: December 2008

ABSTRACT
The effects of a potent gonadotrophin-releasing hormone (GnRH) antagonist, (N-Ac-d-p-Cl-Phe1,2,d-Trp3,d-Arg6,d-Ala10)-GnRH (Org 30276), on pituitary and testicular function of adult macaque monkeys were investigated. After a study to find the correct dose in castrated monkeys, five intact adult male animals were treated with daily s.c. injections of 5 mg antagonist for 9 weeks. The treatment resulted in an immediate decline in serum LH and testosterone in three out of five animals. The two hormones remained suppressed during the 9-week treatment period. Testosterone and LH responses to a bolus injection of GnRH (50 μg i.v.) were blunted or abolished during the antagonist treatment. Testicular volumes decreased markedly and ejaculates obtained at the end of treatment were azoospermic or contained only few dead sperm. Histological examination of the testes showed complete disruption of seminiferous epithelium in these animals. A decrease of body weight was observed in the treated animals. When the treatment was ceased, all inhibitory effects of GnRH antagonists were reversible. In the other two animals no consistent suppression of pituitary or testicular function could be observed during this period, nor was a doubling of the treatment dose for a further 8 weeks capable of fully suppressing endocrine and seminal parameters in these monkeys.
It is concluded that GnRH antagonist treatment is capable of rapidly decreasing serum LH and testosterone and disrupting spermatogenesis in this primate species. Suppression effected by antagonist treatment is more rapid than that caused by GnRH agonists. The individual responses to the tested doses, however, vary markedly.
J. Endocr. (1985) 104, 345–354
Effects of 5-hydroxytryptamine uptake blockers on the release of LH and prolactin in several different experimental steroid models in the rat
Authors: Horn A. M. , Fink G. 
Published: December 2008

ABSTRACT
The effect of the 5-hydroxytryptamine (5-HT) uptake blockers on the surges of LH and prolactin has been investigated in pro-oestrous rats and various experimental models used frequently to study the effects of steroids on LH and prolactin secretion in female rats. The steroid models were: rats ovariectomized on dioestrus, injected immediately with oestradiol benzoate (OB) and at 12.00 h on the next day (presumptive pro-oestrus) with progesterone (model 1); long-term ovariectomized rats injected with a single injection of OB and 72 h later with either progesterone (model 2) or OB (model 3); long-term ovariectomized rats injected daily with OB (model 4). The uptake blockers alaproclate (3–30 mg/kg) and zimelidine (20 mg/kg) were injected and blood samples withdrawn from previously implanted intra-atrial cannulae. Plasma LH and prolactin concentrations were determined by radioimmunoassay. The present study confirmed that a surge of LH occurs at about 17.00–18.00 h of the presumptive day of pro-oestrus in model 1, at about 5 h after (∼ 17.00 h) the injection of either progesterone or the second injection of OB in models 2 and 3, and diurnally in model 4, and the simultaneous occurrence of a prolactin surge in models 2 and 4. A surge of prolactin at the same time as the LH surge was shown to occur also in models 1 and 3. Alaproclate (30 mg/kg) administered at 15.00 h delayed significantly the peak of the prolactin surge in the pro-oestrous rat and models 1, 3 and 4, and in the latter the magnitude of the prolactin surge was also significantly reduced. By contrast, the peak of the prolactin surge in model 2 was significantly prolonged by alaproclate. Alaproclate had no significant effect on either the timing or the magnitude of the LH surge in the pro-oestrous rat, and models 3 and 4. The peak of the LH surge was delayed by alaproclate in model 1 and abolished in model 2, providing further evidence for the possible importance of interactions between 5-HT and progesterone in neuroendocrine control. Zimelidine had no significant effect on either the LH or prolactin surge in the pro-oestrous rat and in models 1 and 2.
These results show that normal 5-HT uptake is necessary for the normal timing and/or magnitude of the spontaneous and steroid-induced prolactin surge but is not essential for the normal timing and magnitude of the spontaneous surge of LH and the LH surge in some but not all steroid models. In terms of neuroendocrine effects alaproclate is more potent than zimelidine. The different effects of alaproclate in the different steroid models suggest that although superficially similar, different mechanisms underlie the prolactin and LH surges in these steroid models.
J. Endocr. (1985) 104, 397–406
Effects of 5-hydroxytryptamine uptake blockers on the concentration in brain of 5-hydroxytryptamine and 5-hydroxyindoleacetic acid in male rats, pro-oestrous rats and ovariectomized rats treated with oestrogen and progesterone
Authors: Horn A. M. , Watts A. G. 
Published: December 2008

ABSTRACT
The aim of this study was to determine the effect of 5-hydroxytryptamine (5-HT) uptake blockade on 5-HT turnover by measuring the concentrations of 5-HT and 5-hydroxyindoleacetic acid (5-HIAA) in brain with the aid of high performance liquid chromatography and electrochemical detection. The indoleamines were measured in the anterior hypothalamus (AH), posterior hypothalamus (PH) and raphe nuclei 30 min after the i.v. injection of either alaproclate (30 mg/kg) or zimelidine (20 mg/kg). The effect of alaproclate was studied in male rats, pro-oestrous female rats, rats ovariectomized and injected s.c. with 20 μg oestradiol benzoate (OB) on dioestrus and at 12.00 h of the next day (presumptive pro-oestrus) with 2 mg progesterone (model 1) and rats ovariectomized 3–4 weeks before an s.c. injection of 20 μg OB followed 72 h later by an s.c. injection of 2 mg progesterone (model 2). Alaproclate caused a significant decrease in the 5-HIAA/5-HT ratio in the AH and PH of the brain of male rats, in the PH and raphe nuclei in pro-oestrous rats and model 1, and in the raphe nuclei alone in model 2. Zimelidine had no effect on the 5-HIAA/5-HT ratio in any area in model 2. In male rats the injection of parachlorophenylalanine produced a marked reduction in the brain concentrations of 5-HT and 5-HIAA, but the 5-HIAA/5-HT ratio was unchanged by a subsequent injection of alaproclate. None of the pharmacological agents affected significantly the brain concentrations of noradrenaline, dopamine or dihydroxyphenylacetic acid.
These results together with the data in the preceding paper show that in female rats changes in LH and prolactin secretion produced by alaproclate may reflect changes in central 5-HT turnover.
J. Endocr. (1985) 104, 407–413
Effects of pup sucking behaviour on inhibition of sexual behaviour and ovulatory secretion of LH in lactating rats
Authors: Lindblom C. , Södersten P. , Eneroth P. 
Published: December 2008

ABSTRACT
The time-interval between parturition and the display of sexual receptivity varied between 13·5 ± 0·7 and 35·9 ± 2·5 days in rats with litters of between 1 and 24 pups. Body weight gain decreased and the avidity of pup sucking behaviour, measured by the latency before the pups, placed on the ventrum of an anaesthetized mother, attached to a nipple of the mother, increased as litter size increased. Litter-shifting procedures, which introduced asynchrony between the lactational age of the mother and the age of the pups, produced deficiencies in sucking behaviour and did not prolong the time-interval between parturition and the display of sexual receptivity by the mother. By keeping the lactational age of the mother in synchrony with the age of the pups and depriving the pups of maternal contact and nutrition every alternate day, the time-interval between parturition and the display of sexual receptivity by the mother was prolonged by 17 days, the avidity of pup sucking behaviour markedly enhanced and the body weight gain of the pups retarded in comparison with mothers and pups continuously living together. The results show that the display of the first postlactational behavioural oestrus and surge of pituitary LH secretion can be greatly delayed by an increase in the avidity of pup sucking behaviour.
J. Endocr. (1985) 104, 419–425
Effects of hypophysectomy and subsequent FSH and testosterone treatment on inhibin production by adult rat testes
Authors: Au C. L. , Robertson D. M. , de Kretser D. M. 
Published: December 2008

ABSTRACT
The hormonal control of inhibin production by adult rat testes was investigated using an in-vitro inhibin bioassay validated for the measurement of inhibin activity in charcoal-treated rat testicular extracts. The effect of hypophysectomy examined at 16 h, 3, 7 and 42 days after surgery showed a decrease in testicular inhibin content and seminiferous tubule fluid production by 7 days and a decrease in inhibin production by 42 days. Serum FSH and LH were suppressed 3 days after surgery. In 30-day chronically hypophysectomized adult rats treated for 3 days with twice daily s.c. injections of (a) human FSH (hFSH, 22 i.u./rat per day), (b) testosterone (5 mg/rat per day), (c) hFSH + testosterone (same doses as a and b), or (d) human chorionic gonadotrophin (hCG, 12 i.u./rat per day), hFSH or hFSH and testosterone stimulated an increase in testicular inhibin content but not in inhibin production or tubule fluid production. Testosterone and hCG had no effect on these parameters.
It is concluded that in vivo, FSH alone stimulates an increase in testicular inhibin content. The failure to observe an increase in inhibin production in vivo is attributed to the suppression of seminiferous tubule fluid production under the same experimental conditions.
J. Endocr. (1985) 105, 1–6
Heterogeneity of rat FSH by chromatofocusing: studies on in-vitro bioactivity of pituitary FSH forms and effect of neuraminidase treatment
Authors: Blum W. F. P. , Riegelbauer G. , Gupta D. 
Published: December 2008

ABSTRACT
This study concerned the resolution of rat pituitary FSH utilizing chromatofocusing. Among the 11 components resolved and positively identified, ten had apparent isoelectric points (pI) between 3·1 and 5·1. Approximately 1% of pituitary FSH eluted at pH 9·4. Treatment with varying amounts of neuraminidase followed by refocusing generated FSH components of higher pI values. Treatment with other glycosidases did not alter the elution characteristics in chromato-focusing, while exclusion chromatography established an inverse relationship between apparent molecular weight and pi. Dose–response curves of various FSH components and of the reference preparation in the current radioimmunoassay system were parallel to each other. A study of their in-vitro bioactivity, utilizing granulosa cells which produce a plasminogen activator due to FSH in a dose-dependent manner, provided the following evidence: increased acidity of the components led to (1) an increase of maximum response and (2) an increase of the dose necessary for half-maximum response. Considering the observed alterations in the hetereogeneity of FSH with changing physiological states of the animal, it is concluded that qualitative changes of the FSH molecule are perhaps involved in a modulatory role in the biopotencies of the hormone.
J. Endocr. (1985) 105, 17–27