bluuebunny/crossref_metadata_2025_split huggingface dataset:
ABNORMAL RESPONSE OF LUTEINIZING HORMONE, FOLLICLE STIMULATING HORMONE AND TESTOSTERONE TO LUTEINIZING HORMONE-RELEASING HORMONE IN CHRONIC RENAL FAILURE
Authors: Hasegawa Koichi , Matsushita Yoshiki , Hirai Kenzo , Otomo Seima , Okamoto Teruo , Morii Hirotoshi , Wada Masahisa 
Published: December 2008

ABSTRACT
Serum levels of LH, FSH, testosterone and oestradiol were measured by radioimmunoassay in 10 healthy subjects and 7 undialysed and 15 dialysed patients with chronic renal failure. The basal level of serum LH was significantly higher in patients with chronic renal failure than in healthy subjects. The basal level of serum FSH in male subjects was significantly higher in dialysed patients with chronic renal failure than in healthy subjects. Regarding testosterone secretion in male subjects and oestradiol secretion in female subjects, it was shown that the basal level of serum testosterone was significantly lower in patients with chronic renal failure than in healthy subjects, and that serum oestradiol levels were within the normal range in most of the patients with chronic renal failure. Serum levels of LH, FSH and testosterone were determined after iv injection of 100 μg of LH-RH in three groups of subjects. Responses of serum LH and FSH to LH-RH were exaggerated and prolonged in patients with chronic renal failure compared with healthy subjects. The peaks of serum LH and FSH were observed 30 min after LH-RH injection in healthy subjects while those in chronic renal failure appeared at 60 to 120 min. The levels of serum testosterone after LH-RH injection did not change within 120 min.
These findings may indicate that the pituitary gonadotrophin response to LH-RH is abnormal and that the turnover of LH, FSH and LH-RH is decreased in patients with chronic renal failure.
THE ACTIVITY OF AN LH-RH-DEGRADING ENZYME IN THE ANTERIOR PITUITARY DURING THE RAT OESTRUS CYCLE AND ITS ALTERATION BY INJECTIONS OF SEX HORMONES
Authors: Kuhl Herbert , Rosniatowski Christian , Taubert Hans-Dieter 
Published: December 2008

ABSTRACT
The basal activity of an LH-RH-degrading enzyme system, L-cystine arylamidase, was determined in the pituitary gland of female rats at 4 h intervals throughout the 4-day oestrus cycle. The activity of the enzyme was found to be fluctuating during the four stages of the cycle in a circadian rhythm with the highest values occurring at night and the lowest values at noon. The maximal activity for the whole cycle was measured at 04.00 h on the day of metoestrus, and the minimal activity between 12.00 h and 16.00 h on the day of pro-oestrus.
The iv injection of various doses of oestradiol caused only a slight change in enzyme activity of the pituitary during oestrus, but considerable increases were observed during the other three stages. The stimulation of enzyme activity by progesterone was much more pronounced during dioestrus and pro-oestrus as compared with metoestrus and oestrus. Similarly the reaction to the injection with LH and prostaglandin E2, repectively, were not very pronounced during oestrus and metoestrus, whereas the enzyme activity rose by +50% and +100%, respectively, during dioestrus and pro-oestrus.
The LH-RH-degrading enzyme system in the pituitary seems to be involved in the control of the tonic LH release, and in the maintenance and regulation of the sensitivity of the gonadotrophs to alterations in LH-RH release from the median eminence.
SYSTOLIC TIME INTERVALS (STI) AS INDICATORS OF MYOCARDIAL THYROID HORMONE EFFECT
Authors: Chakravarty J. , Guansing A. R. , Chakravarty S. , Hughes C. V. 
Published: December 2008

ABSTRACT
Systolic time intervals consisting of indices of electromechanical systole (QS2-I), left ventricular ejection time (LVET-I) and pre-ejection period (PEP-I) were calculated serially during therapy in 12 euthyroid, 9 hypothyroid and 9 hyperthyroid individuals. These parameters were analyzed sequentially together with the changes in serum thyroxine (T4), triiodothyronine (T3) and thyrotrophin (TSH) in order to determine the sensitivity of these non-invasive procedures in monitoring peripheral thyroid hormone effect. The results are expreseed in mean ± sem. QS2-I (506.3 ± 8.2 ms) and PEP-I (102.9 ± 4.2) were shortened (P < 0.02 and P < 0.001, respectively) in hyperthyroidism and prolonged (579.3 ± 7.3 and 169.6 ± 3.6 ms) in hypothyroidism (P < 0.01 and P < 0.001, respectively) compared to euthyroid controls (538.1 ± 8.8 and 130.3 ± 5.3 ms), while LVET-I did not change significantly in either condition. Simultaneous determinations of circulating T4, T3 and TSH showed changes appropriate to both hypo- and hyperthyroid states. In 2 patients with T3-thyrotoxicosis, PEP-I was decreased to an average of 103.1 ms, while in 2 patients with compensated hypothyroidism (normal T4 but elevated TSH) this was prolonged to 163.7 ms (average) compared to euthyroid controls. During treatment the hypothyroid group showed significant sequential correlation of TSH and PEP-I. In the hyperthyroid individuals, PEP-I correlated significantly with T4 and T3. PEP-I may be a useful, sensitive, quantitative biologic indicator of thyroid hormone effect on myocardial function.
DEVELOPMENT OF THE INSULIN SECRETORY DEFECT IN GENETICALLY DIABETIC (db/db) MOUSE
Authors: Berglund Ove , Frankel Barbara J. , Hellman Bo 
Published: December 2008

ABSTRACT
Genetically diabetic mice (C57BL/KsJ-db/db) were used as a model to study the development of defects of insulin secretion in relation to common metabolic indicators (body weight, serum glucose and insulin, and islet insulin contant). Consistent with the idea of a protective effect of oestrogen on the pancreatic β-cell, the female diabetic mice survived longer than the males. In males, while serum insulin decreased in the later stages of the disease, serum glucose increased progressively with age. Perfusion of the diabetic pancreases revealed a rise and subsequent fall with age of the basal insulin released at 3 mm glucose. Despite previous reports of β-cell hyperplasia, progressive impairment of the insulin response to 20 mm glucose, or to 20 mm glucose and 1 mm 3-isobutyl-1-methylxanthine, was seen with increasing age in experiments with perfused pancreas or microdissected islets. Islet content of insulin also decreased progressively with age in the diabetic animals.
THE METABOLISM OF PROSTAGLANDIN E2 BY TISSUES FROM THE HUMAN UTERUS AND FOETO-PLACENTAL UNIT
Authors: Willman Eve A. , Collins W. P. 
Published: December 2008

ABSTRACT
The biosynthesis and metabolism of prostaglandin E2 was studied in cell-free homogenates of tissues from the uterus and foeto-placental unit using specific in vitro methods.
The results show that the synthesis of prostaglandin E2 is greater in endometrial tissue from the secretory phase (53.07 ± 39.05; ng/100 mg wet tissue/h) than from the proliferative phase of the uterine cycle. Furthermore, endometrial tissue forms more of this compound than myometrium (P < 0.005). During early pregnancy, synthesis is decreased (25.10 ± 16.62); at term, myometrium produces more prostaglandin E2 than decidua. During labour, however, decidual tissue accumulates more of this compound (52.73 ± 18.04) than either myometrium (34.71 ± 13.19) or cord (28.63 ± 11.71).
The catabolic enzymes are most active in the placenta and chorion, followed by the cord, myometrium, decidua and amnion, but the differences have only a slight effect on the amounts of prostaglandin E2 which remain at the end of the incubation. The results suggest a high turnover of prostaglandin E2 in the decidua, myometrium and cord.
PYRIDOXINE TREATMENT OF GALACTORRHOEA-AMENORRHOEA SYNDROMES
Authors: Lehtovirta P. , Ranta T. , Seppälä M. 
Published: December 2008

ABSTRACT
The effect of pyridoxine (B6) on galactorrhoea, amenorrhoea, and the galactorrhoea-amenorrhoea syndrome was studied in 22 patients. No consistent change in serum prolactin concentration and no resumption of ovulation were seen during 3 months B6 therapy. Inappropriate lactation ceased in 3 of 10 patients with galactorrhoea alone, and menses were restored in 2 of 9 patients with the galactorrhoea-amenorrhoea syndrome while on B6 therapy. Our results suggest that B6 is not generally effective in the treatment of galactorrhoea-amenorrhoea syndromes.
LONG-TERM TREATMENT OF ACROMEGALY WITH BROMOCRIPTINE
Authors: Eskildsen Peter Claes , Svendsen Per Aaby , Vang Lisbeth , Nerup Jørn 
Published: December 2008

ABSTRACT
Treatment with bromocriptine, 30–55 mg daily, in 13 acromegalics for 1–15 months, resulted in a 60 % decrease in growth hormone secretion, as judged from the excretion of growth hormone in 24-h urine. Normal excretion was obtained in 10 patients, while 1 patient showed no response. The plasma growth hormone response to O-GTT was improved, but not normalized, in 4 of 7 patients treated for more than 6 months, and marked glucosuria disappeared in two diabetics. While the secretion of TSH, LH and FSH was unchanged, the prolactin secretion was inhibited. The urine excretion of free cortisol showed a 30 % decrease, possibly due to a direct effect of bromocriptine on the ACTH-secretion. Hypercalcaemia was never seen, but the initial hypercalcuria showed a modest decrease without measurable changes in the creatinine clearance. The subjective relief during long-term treatment was marked in 10 of 11 patients and the dominating symptoms disappeared in 40–67 %, whereas heal-pad thickness, enlarged sellae, and visual fields remained unchanged. No serious side effects were observed. Treatment with bromocriptine seems effective and should be considered as a remedy amongst others, in suitable cases of acromegaly.
PROLACTIN SECRETION AND SYNTHESIS IN SHORT- AND LONG-TERM ORGAN CULTURE OF PITUITARY TUMOURS FROM ACROMEGALIC PATIENTS
Authors: Peillon F. , Cesselin F. , Garnier P. E. , Brandi A. M. , Donnadieu M. , L'Hermite M. , Dubois M. P. 
Published: December 2008

ABSTRACT
To evaluate the in vitro PRL secretion and synthesis by pituitary tumours from acromegalic patients, six somatotrophic and two somatomammotrophic adenomas were collected after surgery and divided into fragments 1 mm3 in size. Fragments were cultured in short-term (1–2–3–4 h) and in long-term organ culture (7 and 14 days). Media were collected for GH and PRL radioimmunoassay and fragments studied by electron microscopy. In two experiments, fragments from a somatotrophic adenoma and from a somatomammotrophic adenoma were cultured for 1 to 4 h and 9 to 16 days with [3H]leucine. In addition the effect of somatostatin (2.5 nmole/ml) upon PRL secretion was studied in short-term incubation. In long-term organ culture PRL concentrations increased in 8 out of 16 media samples collected from the five tumours and one normal pituitary cultured for 14 days, while GH concentrations decreased during the same time in all the experiments. The [3H]PRL/[3H] proteins ratios were 9.7 % on the 9th day of culture and 20.8 % on the 16th day while for GH, the ratios were respectively 40 and 34.7 %. Ultrastructural studies showed, besides GH cells, the presence of PRL secreting cells in the different tumours, after 7 or 14 days of culture. In short-term incubation, PRL concentrations in media increased in most of the samples collected from the three tumours incubated for 1 to 4 h and the [3H]PRL/[3H]proteins ratio was 10.6 % after 1 h and 21 % after 2 h of incubation. A decrease of PRL content (< 50 %) was observed in two of the three tumours incubated with somatostatin.
These data indicate that 1) somatotrophic adenomas, as well as somatomammotrophic ones, are able to secrete and synthesize PRL in vitro, 2) PRL synthesis from these adenomas increases during culture, as from normal pituitary, presumably because of the release of PRL-secreting cells from the PRL inhibitory hypothalamic control (PIF), 3) somatostatin may reduce PRL release in vitro from somatotrophic adenomas as reported in some cases in vivo.
VASOACTIVE INTESTINAL PEPTIDE (VIP): TISSUE DISTRIBUTION IN THE RAT AS MEASURED BY RADIOIMMUNOASSAY AND BY RADIORECEPTORASSAY
Authors: Besson J. , Laburthe M. , Bataille D. , Dupont C. , Rosselin G. 
Published: December 2008

ABSTRACT
This work was undertaken to study the distribution of VIP in the digestive tract. VIP was measured both by radioimmunoassay and by radioreceptorassay in order to determine whether immunoreactive VIP is related to a biologically active component.
The effect of digestive extracts in inhibiting the binding of porcine [125I]VIP to the antibody (RIA) and to the rat liver plasma membranes (RRA) paralleled that of porcine VIP used as the standard. VIP was found throughout the digestive tract with especially high concentrations between the duodenum (1676 ± 186 ng/g) and the colon (1214 ± 214 ng/g); the maximal quantity occurred in the jejuno-ileum (11 698 ± 687 ng/g). Less than 1 % of VIP was found in the epithelium whereas almost all VIP (> 99%) was localized in the mucosal muscular tissue of the jejunoileum. VIP concentration in the pancreas was 180 ± 26 ng/g of tissue. The VIP contents of the digestive tract were similar when measured either by radioimmunoassay or by radioreceptorassay. Immunoreactive VIP was found in the brain (155 ± 7 ng/g of tissue) and brain extracts competitively inhibited the binding of [125I]VIP (purified from gut) to liver plasma membranes.
These results show that: 1) VIP from the overall gastrointestinal tract is a biological active molecule: 2) VIP from brain binds to receptors for intestinal VIP in liver.
ADRENAL HYPERTROPHY PRODUCED BY 17α-ESTERIFIED GLUCOCORTICOIDS IN RAT FOETUS
Authors: Hasegawa Y. , Okamoto A. , Sakaguchi I. 
Published: December 2008

ABSTRACT
Glucocorticoids were injected sc into rat foetuses through the uterine wall on day 19 of intrauterine development; two days later the foetuses were removed and their adrenal glands were weighed. Some betamethasone derivatives produced marked adrenal hypertrophy in the foetuses. Structural characteristics of the effective compounds were 17α-esterification and 16β-methylation. 9α-Halogenation and 21-esterification of glucocorticoids were not essential for producing the hypertrophy. Propionic acid at the C-17 position was more effective than valeric and acetic acids in producing the hypertrophy. The effect of betamethasone 17, 21-dipropionate was dose-responsive and prevented by simultaneous administration of betamethasone 21-disodium phosphate. Results obtained with decapitated or encephalectomized foetuses suggested that the hypertrophy produced was not due to a direct action of the glucocorticoids on the adrenal gland, but mediated by the hypothalamo-pituitary system.
EFFECT OF POLYAMINES AND THEIR OXIDIZED DERIVATIVES ON THE METABOLISM OF RAT EPIDIDYMAL SPERMATOZOA
Authors: Pulkkinen P. , Piik K. , Koso P. , Jänne J. 
Published: December 2008

ABSTRACT
Spermine and spermidine, occurring at relative high concentrations in the secretions of male sexual glands of various mammals, greatly stimulated the fructolysis in rat epididymal spermatozoa. Calcium likewise had a stimulatory effect on fructolysis producing together with spermine a synergistic enhancement of spermatozoa sugar utilization. While enhancing fructolysis spermine and calcium were practically without any effect on the production of 14CO2 from [2-14C]lactate. Spermatozoal fructose utilization was also markedly increased upon addition of exogenous ATP, spermine producing an additional stimulation with the latter nucleotide.
In addition to spermine and spermidine, the diamines putrescine, 1,3-diaminopropane, cadaverine and histamine also significantly enhanced the formation of radioactive CO2 and lactate from uniformly labelled fructose.
The stimulation of lactate formation by spermine was lost in cell free extracts of spermatozoa. This and the fact that spermine (especially in the presence of ATP) was found to stimulate the uptake of fructose by the epididymal sperm cells suggests that the polyamines interact with cell membranes facilitating sugar uptake.
Oxidized spermine [N,N′-bis(3-propionaldehyde)-1,4-diaminobutane], a compound arising from the action of ruminant plasma amine oxidase, powerfully inhibited both the fructolysis and glycolysis in rat epididymal spermatozoa.
HISTAMINE STIMULATES PROLACTIN RELEASE IN NORMAL MEN
Authors: Pontiroli Antonio E. , Pozza Guido 
Published: December 2008

ABSTRACT
Histamine stimulates prolactin (PRL) and growth hormone (GH) release in the experimental animal. In order to evaluate the possible effect of histamine on these hormones in man, in our study, 9 normal volunteers underwent an intravenous histamine infusion (200 μg in 15 min). Five of them also underwent an intravenous histidine infusion (200 μg). Histamine induced a significant PRL release in 7 subjects, the maximum level reached being 36.2 ± 12.09 ng/ml, while GH levels were not affected. Histidine was ineffective on both PRL and GH levels. It is known that histamine, administered peripherally, does not cross the blood brain barrier. This fact suggests that, in man, histamine stimulates PRL release by acting directly on the pituitary. In addition, since stressful situations may elicit both PRL and GH release, the fact that the latter was not affected by histamine, suggests that a mere stress-effect is not responsible for the PRL release observed in our subjects.
THYROXINE: STUDIES CONCERNING ITS INTRINSIC PHYSIOLOGICAL ACTIVITY
Authors: du Breuil Anne , Galton Valerie Anne 
Published: December 2008

ABSTRACT
The importance of the monodeiodination of T4 to T3 in the physiological action of T4 was explored by assessing the role of T4 in maintaining propylthiouracil (PTU)-treated rats during exposure to 4°C. (PTU inhibits both thyroid hormone biosynthesis and T4 to T3 conversion in peripheral tissues.) Firstly, the effects of cold exposure on the metabolism of T4 in control and PTU-treated rats equilibrated with [125I]T4 (2 μg/100 g b. w./day) were determined. PTU was administered in the food (2 mg/g food). In control rats, no significant changes in T4 metabolism occurred during 3 days at 4°C. Urinary 125I was greatly decreased in PTU-treated rats. Exposure of these rats to cold resulted in some increase but values were still 50 % below normal. Secondly, four groups of rats were exposed to cold: control; PTU-treated; T4-treated; PTU + T4-treated. Control and T4-treated rats survived. PTU-treated rats died unless T4 was administered. Radioimmunoassay of T4 and T3 indicated significant concentrations of T3 in sera of rats from all but the PTU + T4 group. These results suggest that T4 permits survival in the cold-exposed PTU-treated rat without being converted to T3 and thus they support the concept that T4 has intrinsic biological activity.
EFFECTS OF VALINOMYCIN ON Rb+ FLUXES, ATP CONTENT AND INSULIN RELEASE IN PANCREATIC ISLETS
Authors: Idahl Lars-Åke , Sehlin Janove , Täljedal Inge-Bert , Tamarit-Rodriguez Jorge 
Published: December 2008

ABSTRACT
Valinomycin, 0.5–500 nm, was tested for its effects on pancreatic islets microdissected from non-inbred ob/ob-mice. Valinomycin decreased the islet accumulation of Rb+ and the content of ATP in a dose-dependent manner; efflux of Rb+ from pre-loaded islets was not noticeably changed. Rb+ accumulation and ATP content correlated markedly; on the model of linear regression, less than 10% of the change of Rb+ accumulation in valinomycin-treated islets was statistically attributable to factors other than ATP. Valinomycin did not cause a prompt inhibition of glucose-stimulated insulin release that could reflect hyperpolarization due to increased K+ permeability. The following conclusions are drawn: 1) The plasma membranes of β-cells resemble those of neurons in having such a high ion permeability as to be relatively little influenced by valinomycin; 2) Islet accumulation of Rb+ is due to a vectorial catalyst in the plasma membrane rather than to uptake by mitochondria; 3) Rb+ accumulation in islets is ATP-dependent.
PRIMARY INTRACRANIAL HCG-PRODUCING GERMINOMA IN A BOY WITH CONGENITAL ADRENAL HYPERPLASIA
Authors: Levine L. S. , Novogroder M. , Saxena B. , Saenger P. , Saito T. , New M. I. 
Published: December 2008

ABSTRACT
A primary intracranial HCG-producing tumour was studied in an 8 year old boy with congenital adrenal hyperplasia. The case provided a unique opportunity to study the sequential changes in serum and urinary androgens and HCG as measured by radioreceptor assay for HCG and by radioimmunoassay for HCG using antisera raised against the hormone specific for the β subunit of HCG. Plasma concentrations of HCG, measured by the radioreceptor assay, closely correlated with the biologic activity of his tumour, as measured by serum testosterone concentration. This case demonstrates that precocious puberty in any child, including one with a known androgen disorder such as congenital adrenal hyperplasia, warrants thorough investigation.
EFFECTS OF CYCLOHEXIMIDE ON THE ULTRASTRUCTURE OF THE ZONA FASCICULATA OF THE YOUNG RAT ADRENAL
Authors: Magalhães Maria C. , Resende C. , Magalhães M. M. 
Published: December 2008

ABSTRACT
The ultrastructural changes induced in the cells of the young rat adrenal zona fasciculata by cycloheximide are studied. Thirty minutes after administration of doses producing inhibition of protein synthesis (1.5 and 4.5 mg/kg body weight) there was a significant increase in the relative volume of the nucleolus, as shown by stereologic methods, which was accompanied by extensive perinucleolar chromatin caps. In the cytoplasm, membranous whorls were observed in several organelles and the background cytoplasm, but the volume fractions of the organelles were not significantly altered. Nucleolar changes were interpreted as suggesting that the inhibition of cytoplasmic protein synthesis may be accompanied by an enhanced formation of nucleolar proteins.
USE OF HPLC TO DETERMINE THE EFFECT OF 17β-HYDROXY-7α-METHYLANDROST-5-EN-3-ONE (RMI 12,936) ON PRODUCTION OF PROGESTERONE BY RAT OVARIAN HOMOGENATE
Authors: Taylor R. B. , Kendle K. E. 
Published: December 2008

ABSTRACT
A new high pressure liquid chromatography (HPLC) method for the determination of progesterone in the presence of other Δ43-ketosteroids is described. Using this method it is shown that the rate of production of progesterone from pregn-5-ene-3,20-dione by rat ovarian homogenate is initially rapid but falls to zero within 10 min. Experiments indicate that the inhibition is due to the progesterone formed. Inclusion of RMI 12,936 with the pregn-5-ene-3,20-dione substrate results in a lower final level of progesterone and continuous production of 7α-methyltestosterone. The reduction in the levels of progesterone in presence of RMI 12,936 corresponds closely to the reduction in plasma progesterone in vivo following administration of RMI 12,936 described preivously.