bluuebunny/crossref_metadata_2025_split huggingface dataset:
ANTIGOITROGENIC EFFECT OF CASEIN
Authors: Gaitán Eduardo , Merino Héctor 
Published: December 2008

ABSTRACT
Epidemiological findings from the city of Cali, Colombia, support the hypothesis that water supply and iodine intake are not the only dietary factors which influence the magnitude of the goitre endemia. Experiments were conducted in rats to determine whether casein has a counteracting effect on the goitrogenic and antithyroid activities of methimazole (MMI) and goitrogenic water extracts (GWE) from the endemic area of the Cauca Valley. Female albino rats (Charles River, DC strain) 100–110 g initial weight, receiving 12 μg of iodine daily, were divided into three groups and put on special diets: protein-free, 8% casein, or 60% casein, respectively. Each group (24 rats) was then divided into three subgroups. Subgroup one received goitrogen-free water and was used as a control. Subgroup two was administered MMI, 50 μg/day/rat. Subgroup three was given per animal a daily amount of GWE equivalent in antithyroid potency to 50 μg of MMI. At 77 days, the thyroid glands were studied for weight, 131I uptake, and 127I concentration. Animals on the protein-free diet showed significantly (P < 0.05 – < 0.01) larger thyroid glands per 100 g body weight and lower thyroidal 4 h 131I uptake and 127I-concentrations than rats on casein diets. These differences were significantly increased (P < 0.01) by the administration of MMI and GWE. All the effects were completely reversed by the 60 % casein diet showing no differences between control rats and those on MMI or GWE. Rats on 8 % casein showed intermediate values between those of animals on protein-free and 60% casein diets; differences were still present between the control as against the MMI or GWE groups. The results indicate that under these experimental conditions, a poor-protein diet impairs the thyroidal transport of iodine, decreases its concentration in the thyroid and is accompanied by an enlargement of the gland. Under these circumstances, the action of thiourea-like antithyroid agents is enhanced. The administration of protein reverses these alterations and decreases the action of such antithyroid agents. Whether the changes observed are due to a direct action of casein on the thyroid and/or to effects of malnutrition on the metabolism of antithyroid compounds remains to be determined.
IMMUNOREACTIVE ACTH, IMMUNOREACTIVE HUMAN CHORIONIC SOMATOMAMMOTROPHIN (HCS) AND 11-OH STEROIDS PLASMA LEVELS IN NORMAL AND PATHOLOGICAL PREGNANCIES
Authors: Genazzani A. R. , Felber J. P. , Fioretti P. 
Published: December 2008

ABSTRACT
Plasma immunoreactive ACTH (I. R. ACTH), immunoreactive human chorionic somatomammotrophin (I. R. HCS) and 11-OH steroids levels were measured during normal and pathological pregnancies. Plasma I. R. ACTH levels were found to be above normal during pregnancy, with a slight decrease near term. This observation correlates well with the recent description of human chorionic corticotrophin (HCC), i. e. a factor of placental origin possessing a high biological adrenocorticotrophic activity and presenting partial immunological cross-reaction with human ACTH. The 11-OH steroids levels, as measured by a fluorimetric method, increased regularly during pregnancy but, unlike ACTH, reached their highest value near term, I. R. HCS increased progressively until term when a slight decrease was observed.
In pathological pregnancies, I. R. ACTH levels behaved like other placental hormones. On the contrary, 11-OH steroids levels remained generally unmodified. Treatment with high doses of prednisolone caused no inhibition of the plasma I. R. ACTH and of plasma 11-OH steroids levels. These data suggest placental autonomy of the secretion of HCC and low adrenal responsiveness to endogenous ACTH variations throughout pregnancy.
EFFECT OF AN ANABOLIC STEROID (METANDIENON) ON PLASMA LH, FSH, AND TESTOSTERONE AND ON THE RESPONSE TO INTRAVENOUS ADMINISTRATION OF LRH
Authors: Holma Pentti , Adlercreutz Herman 
Published: December 2008

ABSTRACT
Plasma levels of testosterone, luteinizing hormone (LH) and follicle-stimulating hormone (FSH) as well as the response of LH and FSH to the intravenous administration of 100 μg of luteinizing hormone releasing hormone (LRH) were measured in 16 well-trained athletes (mean age 30 years) before and after 2 months of daily oral intake of 15 mg of metandienon, an anabolic steroid (Anabolin®, 17α-methyl-17β-hydroxy-1,4-androstadien-3-one, Medica, Finland). All athletes continued to train regularly, just as they had done for several years.
During administration of metandienon the mean plasma testosterone level fell 69%, from 29.4 ± 11.6 nmol/l to 9.1 ± 7.5 nmol/l. The mean plasma levels of LH and FSH also fell significantly (P < 0.001 and P < 0.01, respectively), both about 50%. Because LH and FSH levels were low after administration of the steroid the maximum stimulation values after LRH administration were also lower than pre-treatment values although the mean increments did not differ significantly before and after administration of the anabolic steroid. However, after treatment, the FSH response curve had a biphasic pattern in most subjects, with peaks at 10 to 20 and 50 to 60 min after the iv injection of LRH. Administration of LRH after the treatment period had no effect on FSH secretion in two subjects and no effect on LH secretion in one. Our results show that administration of an anabolic steroid causes a pronounced lowering of plasma levels of testosterone, LH and FSH but causes no gross alteration in the response of LH secretion to stimulation by LRH. The reason for the biphasic response pattern of FSH to LRH administration in most subjects is not known.
ANTIGONADOTROPHIC EFFECT OF PROLACTIN IN ADULT CASTRATED AND IN IMMATURE FEMALE RATS
Authors: Beck W. , Engelbart S. , Gelato M. , Wuttke W. 
Published: December 2008

ABSTRACT
High serum prolactin levels were induced in chronically castrated female rats by pituitary transplants from male donor rats. The typical pulsatile LH release pattern observed in castrated control rats was maintained in pituitary grafted rats, when pituitary transplantation was performed simultaneously with castration 3 months before withdrawal of the blood samples. If pituitaries were transplanted into chronically castrated rats and blood samples were withdrawn 3 days later, the pulsatile LH release was abolished and basal or moderately elevated LH levels were found. Chronically or subacutely elevated prolactin levels had no effect on high serum FSH values.
Pituitary transplants into intact female rats at day 23 after birth also suppressed basal LH values for 4 days without alterating the serum FSH levels. Six and 8 days after transplantation the serum LH levels were normal. Pituitary transplantation into these immature rats advanced puberty by more than one week.
These results indicate that prolactin has an antigonadotrophic effect in female rats which is directed only towards pituitary LH but not FSH secretion. The inhibitory action of high serum prolactin levels on pituitary LH release does not last longer than 4–6 days under steady state conditions, such as found in the constantly high prolactin levels due to pituitary transplants. Under natural conditions with steadily increasing prolactin levels between day 20 and puberty the effect of prolactin in inhibiting pituitary LH release may last longer. Thus, prolactin may be one of the, if not the regulator of the timing of puberty.
ADRENAL ACTIVITY DURING NORMAL GLUCOSE TOLERANCE
Authors: Sober Arthur J. , Ruder Henry J. , Sode Jonas 
Published: December 2008

ABSTRACT
Plasma cortisol was measured by radioimmunoassay during 4 h oral glucose tolerance tests in 8 non-obese normal subjects. Following 100 g of glucose, plasma cortisol concentrations were lower than basal at 15, 30 and 60 min, and declined with a half-time of 70 min. No evidence was obtained that the hyperglycaemia which follows glucose ingestion leads to increased cortisol secretion and that such a mechanism is involved in the stabilization of blood sugar levels during the posthyperglycaemic phase of the normal oral glucose tolerance test. Epinephrine and norepinephrine excretory rates during the hyperglycaemic (0–2 h) and euglycaemic (2–4 h) phases of the test were not significantly different. It is concluded that adrenocortical and adrenomedullary activities are not increased during normal glucose tolerance in man.
GUSTATORY-ALIMENTARY REFLEX INHIBITION OF ALDOSTERONE HYPERSECRETION BY THE AUTOTRANSPLANTED ADRENAL GLAND OF SODIUM DEFICIENT SHEEP
Authors: Denton D. A. , Blair-West J. R. , Coghlan J. P. , Scoggins B. A. , Wright R. D. 
Published: December 2008

ABSTRACT
Several experimental investigators have reported that stimulation of gustatory and alimentary afferents may rapidly influence metabolic and endocrine processes. Changes may precede absorption of materials ingested and anticipate the physiological consequences. A colony of sheep with autotransplanted adrenal glands and a permanent unilateral parotid fistula, have been studied over a perior of 12 years. The effect on corticosteroid secretion of rapid satiation of salt appetite after 24–72 h of sodium depletion has been observed. The animals drank 300–900 mmol of NaHCO3 solution in 5–20 min. Rapid voluntary intake of NaHCO3 caused large evanescent reduction of aldosterone hypersecretion for the 15–36 min following satiation. Aldosterone secretion rebounded by 1 h towards control pre-drinking level. It then fell over 2–5 h to the Na+ replete range as a result of absorption from the gut of the sodium ingested. The satiation inhibition was seen in the majority, but not all sheep who had had a parotid fistula for several years. The effect was reproducible in the one animal over as long as six years.
Analysis of the mechanism showed that it was not due to change of the four factors currently known to be implicated in control of aldosterone secretion viz. plasma [Na], [K], angiotension II and ACTH. The data indicates the action of an unidentified factor in the control of aldosterone secretion - possibly an inhibitor substance originating in the brain.
DIFFERENTIAL DISTRIBUTION OF OESTROGEN RECEPTORS IN SUBFRACTIONS OF OVIDUCT CHROMATIN
Authors: Hemminki Kari 
Published: December 2008

ABSTRACT
DNase II shearing and MgCl2 precipitation of chick oviduct chromatin were applied to prepare fractions which resembled template-active and template-inactive chromatin fraction as described for other tissues. The labelling of these preparations with [3H]oestradiol was studied in short-term tissue cultures. The MgCl2 soluble (∼ template-active) chromatin bound 1.8 times more oestradiol than the MgCl2 insoluble chromatin when immature chicks were used. The proportion was 4.3-fold in oestrogen stimulated chicks and 4.6-fold in laying hens. Similar results were obtained with an oestrogen exchange assay which measured the concentration of endogenous receptors. These data suggest that hormone stimulation is accompanied by a selective activation of oviduct chromatin leading to an enrichment of acceptor sites for oestradiol receptors in the template-active chromatin fraction.
LUTEINIZING HORMONE RESPONSES TO LUTEINIZING HORMONE RELEASING HORMONE, AND GROWTH HORMONE AND CORTISOL RESPONSES TO INSULIN INDUCED HYPOGLYCAEMIA IN FUNCTIONAL SECONDARY AMENORRHOEA
Authors: Hirvonen E. , Seppälä M. , Karonen S.-L. , Adlercreutz H. 
Published: December 2008

ABSTRACT
Luteinizing hormone (LH) responses to luteinizing hormone releasing hormone (LHRH), and growth hormone (GH) and cortisol responses to insulin induced hypoglycaemia were studied in 56 women classified into 4 distinct groups of functional secondary amenorrhoea. The groups were: I, self-induced weight reduction (20 patients); II, post pill amenorrhoea (14 patients); III, anorexia nervosa (10 patients); and IV, idiopathic secondary amenorrhoea (12 patients). Only patients with no overlapping anamnestic factors were included.
Group I patients had the most heavily impaired LHRH-LH responses, and the GH response to hypoglycaemia was smaller than in other groups. Cortisol responses were normal. Group II patients showed blunted LH responses and normal GH and cortisol responses. Group III patients showed normal or exaggerated LH responses in the recovery phase of anorexia nervosa, while those two patients who were in the static phase of the illness had impaired responses. GH responses varied greatly. Group IV patients had normal basal levels of LH and normal LH, GH and cortisol responses.
The restoration of LH response is not solely correlated to body mass, since patients recovering from anorexia nervosa showed greater LHRH-LH responses with nutritional rehabilitation at 76% of ideal body weight than patients with self-induced weight reduction at 87% of ideal body weight. In idiopathic amenorrhoea the hypothalamic pituitary axis seems to be practically intact.
The function of hypothalamic-pituitary axis may be impaired selectively in functional amenorrhoea. Corticotrophin releasing hormone function remains intact, and GH-response may be impaired or normal independently of the LH-response to LHRH. In self-induced weight reduction both functions were impaired. These tests are easily carried out with outpatients, and they give more information about the functional state of hypothalamic-pituitary axis than basal analyses of gonadotrophins and oestrogens. However, a single pathologic reading in the LH response is not specific enough to indicate to which group of amenorrhoea the patients belong, but these tests together elucidate the severity of lesion in hypothalamic pituitary axis.
PROLACTIN LEVELS IN THE INSULIN TOLERANCE TEST WITH AND WITHOUT PRE-TREATMENT WITH DEXAMETHASONE
Authors: Osterman P. O. , Fagius J. , Wide L. 
Published: December 2008

ABSTRACT
The serum prolactin response to insulin-induced hypoglycaemia was studied in 20 healthy volunteers. The results of insulin tolerance tests performed after pre-treatment with dexamethasone in a dose of 0.5 mg (0.5-DEX-ITT) and 1.0 mg (1.0-DEX-ITT) were compared with those of a similar control insulin tolerance test (ITT). The serum prolactin levels increased in all but 3 ITT's. In the ITT and 0.5-DEX-ITT the prolactin responses were significantly greater in women than in men. After pretreatment with dexamethasone the basal serum prolactin levels and the prolactin response to hypoglycaemia were significantly decreased compared with those in the ITT. The prolactin response both to insulininduced hypoglycaemia and to dexamethasone showed such a large individual variation that this type of response seems unsuitable for evaluation of the hypothalamo-pituitary function.
RESPONSE OF THE PITUITARY-TESTICULAR AXIS TO LUTEINIZING HORMONE-RELEASING HORMONE IN THE IMMATURE MALE RAT
Authors: Grotjan H. Edward , Johnson Donald C. 
Published: December 2008

ABSTRACT
Follicle stimulating hormone (FSH), luteinizing hormone (LH), testosterone and androstenedione were measured by radioimmunoassays in the sera of immature male rats treated with luteinizing hormone-releasing hormone (LH-RH). A single dose of 10, 20, 40 or 80 ng of LH-RH produced a prompt increase in serum LH: significant changes in FSH were found only with the two larger doses. Serum testosterone increased to peak levels in 20 to 40 min and returned to control level by 120 min. Changes in androstenedione were temporally similar but smaller in magnitude. Four doses of 20 or 40 ng LH-RH given at 20 min intervals did not increase serum LH or testosterone concentrations above those found with a single injection; FSH was slightly higher after the fourth dose. However, 40 ng LH-RH given every 20 min for 2 h produced a dramatic increase in serum LH and FSH: serum and testicular androgens were also much higher during the second hour. A 2 h stimulation with 80 ng LH-RH given ip at 30 min intervals did not alter the response to the same treatment given 24 h later; i. e., neither the pituitary nor the gonad was primed by previous exposure to increased levels of LH-RH or gonadotrophins. These results suggest that a single pulse of LH-RH produces a predictable response in the animal, but multiple episodic stimuli produce variable responses: testes, on the other hand, produce androgens as long as gonadotrophins are available.
ACTION OF CYCLIC NUCLEOTIDES ON PROTEIN AND RNA SYNTHESIS IN THE THYROID
Authors: Pisarev Mario A. , de Pisarev Diana L. Kleiman 
Published: December 2008

ABSTRACT
Thyrotrophin (TSH) regulates the biosynthesis of thyroid protein and RNA. This action is mediated by adenylate cyclase and cyclic AMP. In the present study the action of cyclic GMP and cyclic CMP was investigated in beef slices. Both cyclic AMP and cyclic GMP significantly increased the incorporation of [3H]uridine into RNA. These effects were blocked by actinomycin D, suggesting that their action is located at a preor at a transcriptional step. The PCA soluble fraction radioactivity followed in parallel with the variations observed in the RNA fraction, supporting the view that cyclic nucleotides may regulate RNA by modulating the nucleotide precursors pool.
Cyclic CMP in concentrations between 0.35 to 1.5 mm progressively decreased the RNA labelling, and the values of the PCA soluble radioactivity again followed those of RNA. Furthermore, cyclic CMP also blocked the in vitro stimulatory action of cyclic AMP on the incorporation of [3H]leucine into protein, and of [3H]uridine into RNA. The present results provide the first information on the action of cyclic AMP on RNA synthesis and suggest that negative signals may also play a part in the regulation of thyroid function.
THE INFLUENCE OF COMBINED CYPROTERONE ACETATE-ETHINYL OESTRADIOL THERAPY ON SERUM LEVELS OF DEHYDROEPIANDROSTERONE, ANDROSTENEDIONE, AND TESTOSTERONE IN HIRSUTE WOMEN
Authors: Frölich Marijke , Lachinsky Nadia , Moolenaar A. J. 
Published: December 2008

ABSTRACT
Serum levels of dehydroepiandrosterone, androstenedione, and testosterone in hirsute women suffering from either idiopathic hirsutism or the polycystic ovary syndrome were determined before and during treatment with cyproterone acetate combined with ethinyl oestradiol. During this treatment the hirsutism decreased markedly. In untreated hirsute women serum dehydroepiandrosterone levels do not differ from those in normal women and do not change during therapy; androstenedione levels are higher than normal and decrease markedly during treatment, and the testosterone levels are elevated compared to normals, with a considerable overlap, and show only a tendency to decrease. There is no correlation between dehydroepiandrosterone and androstenedione levels or between androstenedione and testosterone levels in the serum of untreated hirsute women. After 12–14 months of cyproterone acetate-ethinyl oestradiol therapy a linear correlation is found between dehydroepiandrosterone and androstenedione levels. This can be explained by the relatively higher contribution of the peripheral conversion of dehydroepiandrosterone to androstenedione to the occurrence of lower androstenedione levels. The linear correlation between androstenedione and testosterone after treatment, also found in normal women, indicates the restoration of the role of androstenedione as the major peripheral precursor of testosterone.
THE EFFECT OF PITUITARY-ADRENAL MANIPULATIONS UPON URINARY CYCLIC AMP EXCRETION IN MAN
Authors: Perlstein Robert , Kopp Lowell , Tucci Joseph R. 
Published: December 2008

ABSTRACT
The present studies demonstrate that the administration of pharmacologic amounts of ACTH is associated with small but significant increases in urinary cyclic AMP excretion and in urinary cyclic AMP/creatinine ratios which are most likely related to a release of cyclic AMP from adrenocortical tissue. Acute suppression of the pituitary-adrenal axis with dexamethasone and stimulation with metyrapone, however, is not associated with changes in urinary cyclic AMP excretion. These results suggest that physiological levels of ACTH and cortisol contribute little, if any, to the urinary excretion of cyclic AMP in man.
THE PLASMA CONCENTRATIONS OF TESTOSTERONE AND LH DURING THE OVULATION CYCLE OF THE HEN (GALLUS DOMESTICUS)
Authors: Etches R. J. , Cunningham F. J. 
Published: December 2008

ABSTRACT
The plasma concentrations of testosterone and luteinizing hormone (LH) were measured by radioimmunoassay during the ovulation cycle of the hen. The baseline concentrations of testosterone were 100 to 250 pg/ml and the maximum concentration of 904 pg/ml was observed 8 h before ovulation. The maximum pre-ovulatory concentration of LH of 2.0 ng/ml, which was approximately twice the basal concentration, was observed 6 h before ovulation. The possibility that testosterone is the ovarian excitation hormone which initiates the ovulation-inducing surge of LH is discussed.
MAMMOTROPHIC ACTIVITY IN RAT AMNIOTIC FLUID
Authors: Peters J. M. 
Published: December 2008

ABSTRACT
Mammotrophic activity was present in rat amniotic fluid collected on days 13, 15 and 19 of pregnancy. The mammotrophic activity in the fluid was equivalent to that in the maternal serum on day 15, but is was lower on day 19. The effect of the amniotic fluid was similar to that of human placental lactogen on the rat mammary gland in vitro. The prolactin concentration in the amniotic fluid was low (approximately 1 ng/ml).
PREVENTION BY MELATONIN OF SHORT DAY INDUCED ATROPHY OF THE REPRODUCTIVE SYSTEMS OF MALE AND FEMALE HAMSTERS
Authors: Reiter R. J. , Vaughan M. K. , Waring P. J. 
Published: December 2008

ABSTRACT
Male and female hamsters were exposed to natural photoperiodic and temperature conditions beginning on November 13 and groups of hamsters were necropsied either on January 15 or on April 10. Throughout the study, half of the hamsters (control hamsters) received subcutaneous implants of beeswax (25 mg) every other week while the other half received beeswax pellets containing 1 mg melatonin. Control beeswax-treated males necropsied in January had atrophic testes and accessory sex organs while the uteri of the control females were infantile in appearance. Melatonin treatment prevented the atrophic responses of the testes and accessory sex organs in males and the uteri in females. Melatonin-treated hamsters killed in January also had higher plasma levels of immunoreactive LH while in females both pituitary and plasma levels of LH were elevated after melatonin treatment. By April 10, the testes and accessory organs of control males and the uteri of control females had regenerated to the adult condition and these organs were comparable in size to those in melatonin-treated hamsters. The pituitary glands of control males contained slightly more LH and much more FSH than the pituitaries of melatonin-treated males. Melatonin-treated females necropsied in April had pituitary and plasma levels of LH and FSH similar to those in beeswax-treated females killed at the same time. The data show that chronic melatonin treatment prevents atrophy of the reproductive organs of male and female hamsters which is associated with the shortened days of the winter.
BLINDING AND PINEALECTOMY IN MALE HAMSTERS: EFFECTS OF PINEAL INDOLES AND P-CHLOROPHENYLALANINE ON TESTES, SEMINAL VESICLES, PITUITARY AND ADRENAL GLANDS
Authors: Bush Francis M. , Seibel Hugo R. 
Published: December 2008

ABSTRACT
No antigonadotrophic (AGT) activity was found after injecting 5 methoxytryptophol (5 MTPH) or both serotonin and melatonin simultaneously in normal male hamsters or hamsters subjected to blinding, pinealectomy, or both surgical procedures. Treatment with these indoles did not induce changes in weights of testes, seminal vesicles, pituitary or adrenal glands. Reproductive organs in hamsters blinded by enucleation atrophied in spite of daily consumption of the vasodilator, Apresoline. Feeding of p-Chlorophenylalanine (PCPA) revealed this antagonist to be mildly toxic. PCPA seemed to interfere in the hypophyseal-adrenal axis: these hamsters lost the most weight, pituitary glands were enlarged and some hyperactivity occurred in the hamsters.