bluuebunny/crossref_metadata_2025_split huggingface dataset:
ACTH STIMULATES LATE STEPS IN CORTISOL BIOSYNTHESIS
Authors: McKenna Terence J. , Island Donald P. , Nicholson Wendell E. , Miller Rebecca B. , Lacroix Andre , Liddle Grant W. 
Published: December 2008

ABSTRACT
Acute stimulation of steroidogenesis with ACTH produces striking elevations in the plasma levels of cortisol as well as certain cortisol precursors. However, although states of chronic ACTH excess are characterized by similar elevations in cortisol, the precursor levels are in the low normal range. We have previously proposed that chronic stimulation of adrenal steroidogenesis with ACTH may enhance the activity of the late phase of cortisol biosynthesis. Precursor steroids would then be more efficiently used with less precursor leakage from the cell and greater cortisol production. In the present study, we have examined the effect of ACTH on the late phase of cortisol biosynthesis in vitro using bovine adrenal cell suspensions. To exclude the well established effect of ACTH on early cortisol biosynthetic steps we treated the cell suspensions with aminoglutethimide. This agent inhibits the conversion of cholesterol to pregnenolone and therefore to cortisol, both under basal conditions and during treatment with ACTH. To aminoglutethimide-treated cell suspensions, we added pregnenolone, 1 7-OH-pregnenolone, progesterone, 17-OH-progesterone and 11-deoxycortisol, with and without ACTH. In the presence of ACTH, significantly more cortisol was formed from progesterone, 17-OH-progesterone, and 11-deoxycortisol. To distinguish between effects of ACTH on the entry of precursors into cells and on enzyme activity within the cells, we examined the conversion of 11-deoxycortisol to cortisol in homogenized cell suspensions with and without pre-treatment with ACTH. Even in homogenized cells, prior treatment with ACTH enhanced the conversion of 11-deoxycortisol to cortisol. These findings clearly demonstrate that ACTH has a direct effect on the late phase of cortisol biosynthesis.
STUDIES ON CYCLIC NUCLEOTIDES IN THE ADRENAL GLAND
Authors: Shima Sumio , Kawashima Yoshiko , Hirai Masanao 
Published: December 2008

ABSTRACT
Effects of ACTH and calcium on cyclic AMP and steroid production by the zona fasciculata-reticularis (the decapsulated fraction) from the rat adrenal cortex have been studied. Increasing concentrations of extracellular calcium enhanced the action of ACTH on cyclic AMP and steroid production. These effects of ACTH with calcium were prevented by lanthanum, but not by tetracaine or verapamil, suggesting that ACTH stimulation may be mediated by calcium through a process not involving the tetracaine- or verapamil-vulnerable step(s) of the calcium current.
High concentrations of external calcium itself increased cyclic AMP accumulation without any increase in steroidogenesis. A calcium ionophore, X537A was stimulatory for steroidogenesis but inhibitory with respect to cyclic AMP accumulation. Considered together with the findings of steroidogenic stimulation by low concentrations of ACTH without cyclic AMP increase, these results suggest that ACTH primarily increases intracellular calcium mobilization thus stimulating directly the steroidogenesis, which is independent of the cyclic AMP system. Relatively high concentrations of ACTH activate the adenylate cyclase, which depends on extracellular calcium to increase cyclic AMP levels and stimulation of steroidogenesis by the decapsulated fractions of the adrenal cortex.
PURIFICATION OF "INHIBIN" FROM HUMAN OVARIAN FOLLICULAR FLUID
Authors: Chari S. , Hopkinson C. R. N. , Daume E. , Sturm G. 
Published: December 2008

ABSTRACT
Following the earlier demonstration of inhibin-like activity in human ovarian follicular fluid a method for its purification to apparent homogeneity is described. The fluid was converted to acetone powder and subjected sequentially to ammonium sulphate fractionation, gel chromatography on Sephadex G-200, continuous gradient ion-exchange chromatography on DEAE-cellulose, first with a pH gradient from 8.0 to 4.0 and then with a NaCl gradient to 1 m at pH 5.2. The active fraction from this step was subjected to gel filtration on Sephadex G-100 and finally passed through an Amicon Centriflo membrane CF-25 (cut off point: 25 000 m.w.). The ultrafiltrate was homogeneous by SDS-polyacrylamide gel electrophoresis, had a molecular weight of the order of 23 000 and was capable of suppressing serum gonadotrophin levels in the castrated male rats in as low a dose as 25 μg/rat.
INSULIN RECEPTORS, INSULIN SECRETION, AND GLUCOSE DISAPPEARANCE RATE IN PATIENTS WITH PERIODIC HYPOKALAEMIC PARALYSIS
Authors: Johnsen Torsten , Beck-Nielsen Henning 
Published: December 2008

ABSTRACT
In a study of 6 male patients with periodic hypokalaemic paralysis (PHP), we found reduced insulin binding to monocytes as compared with a group of 25 normal subjects (P < 0.1). The decreased insulin binding was caused by the decreased binding affinity.
During induction of paralysis by a prolonged oral glucose load, one patient showed 24-h variations in the insulin binding to monocytes not differing from those observed in normals. After iv administration of glucose, these patients showed an elevated initial insulin response compared with the normals (P < 0.1). However, the iv glucose tolerance tests revealed normal glucose disappearance rates.
We conclude that changes in insulin receptor binding do not appear to be of pathophysiological significance for eliciting the parese attacks in PHP. However, the increased insulin response, following carbohydrate intake, might be of significance in the generation of paralytic attacks in patients with PHP.
OVARIAN BINDING AND INTRINSIC BIOLOGICAL ACTIVITY OF DESIALYLATED HUMAN CHORIONIC GONADOTROPHIN (ASIALO-hCG) IN IMMATURE SUPEROVULATED RATS
Authors: Odink J. , Brand E. C. , Van Hall E. V. 
Published: December 2008

ABSTRACT
The present study was undertaken to investigate the effect of desialylation on the intrinsic in vivo biological activity of hCG. To block the hepatic uptake of asialo-hCG we investigated asialo-orosomucoid. The biological activity of hCG and asialo-hCG was estimated with the ovarian ascorbic acid depletion assay (OAAD). The uptake studies were performed with [125I]hCG and [125I]asialo-hCG.
Desialylation of hCG increased its hepatic uptake, almost completely abolished its ovarian uptake, and reduced its in vivo biological activity to less than 1 %. Administration of asialo-orosomucoid caused a reduction of the hepatic uptake of asialo-hCG to the level observed for hCG. The ovarian uptake increased, but was lower than observed for hCG, due to a considerably higher renal accumulation of asialo-hCG. The in vivo biological activity of asialo-hCG was approximately 1/5 of the activity of hCG when both were tested in the presence of asialo-orosomucoid.
To exclude the interference of renal accumulation, binding and biological activity were also investigated after bilateral nephrectomy. The uptake of radioactivity in the ovaries following injection of [512I]asialo-hCG and asialo-orosomucoid was then almost the same as observed after injection of [125I]hCG alone. When both preparations were now tested in the presence of asialo-orosomucoid, the in vivo biological activity of asialohCG appeared to be approximately 1/3 of the value obtained for hCG. It is concluded that the intrinsic in vivo biological activity of hCG is lowered by desialylation.
THE INFLUENCE OF AMINO ACIDS AND SOMATOSTATIN ON PROLACTIN AND GROWTH HORMONE RELEASE IN MAN
Authors: Bratusch-Marrain P. , Waldhäusl W. 
Published: December 2008

ABSTRACT
The effect of an iv load of individual amino acids (alanine, arginine, histidine, leucine, phenylalanine, and valine) on serum prolactin (Prl) and growth hormone (GH) concentrations was studied in healthy adult males (n=5). A rise in both, Prl and GH with a maximal increment of 15.9±6.7 (se) ng/ml, and 12.4±4.9 ng/ml above basal levels, respectively, (P< 0.05) was observed after iv arginine. Following iv phenylalanine the mean peak level of Prl rose from 9.9 ± 3.5 to 29.9 ± 7.3 ng/ml (P <0.01), whereas GH concentration remained unchanged. Iv leucine however induced an immediate rise in GH, but not in serum Prl. Serum concentrations of both, Prl and GH, failed to increase upon the infusion of either alanine or histidine or valine. Additional somatostatin administration starting prior to amino acid infusion diminished the amino acid induced increase of both Prl and GH release.
THE EFFECT OF FOOD INTAKE ON INSULIN RECEPTOR IN MAN
Authors: De Pirro R. , Bertoli A. , Greco A. V. , Gelli A. S. , Lauro R. 
Published: December 2008

ABSTRACT
Insulin binding to circulating monocytes was studied in 22 normal volunteers before and 1, 3 and 5 h after a 1400 Kcal meal.
Results indicate that 3 h after food intake there is an increase in the specific cell binding fraction (P < 0.001) with a change in receptor affinity. Data emerging from the present study demonstrate that there are rapid changes in insulin receptor properties during the day. These changes probably play a role in the regulation of the hormonal and metabolic pattern in normal subjects.
NSILA AND FOETAL GROWTH
Authors: Heinrich U. E. , Schalch D. S. , Jawadi M. H. , Johnson C. J. 
Published: December 2008

ABSTRACT
Employing a sensitive competitive protein binding assay for NSILA (non-suppressible insulin-like activity), circulating levels of this somatomedin (SM) have been measured throughout pregnancy, at parturition, and in foetal and newborn sera. Acid-dissociable serum NSILA (mean ± sem) in 57 women was significantly higher during pregnancy (1106 ± 46 μU/ml), than in 11 adult non-pregnant control subjects (844 ± 22 μU/ml), but not correlated with week of gestation or with serum growth hormone (GH) or cortisol levels. At parturition, the NSILA concentration in 28 cord sera (598 ± 38 μU/ml) was significantly less than in the corresponding maternal sera (1039 ± 63 μU/ml). The NSILA levels in 23 premature newborns (370 ± 20 μU/ml) and 8 smallfor-gestational-age newborns (310 ± 46 μU/ml) were significantly less than in 33 term newborns (494 ± 18 μU/ml). Serum NSILA in 56 term and premature newborns exhibited a significant positive correlation both with gestational age and birth weight but not with serum GH or cortisol levels. These data suggest that the maternal-foetal growth-promoting system is a highly complex one in which NSILA levels both in maternal and foetal circulations appear to be under multifactorial control.
ENDOCRINE TESTICULAR FUNCTION IN VIVO AND IN VITRO IN INFERTILE MEN
Authors: Nieschlag E. , Wickings E. J. , Mauss J. 
Published: December 2008

ABSTRACT
In order to detect any possible Leydig cell dysfunction associated with male infertility, the endocrine capacity of the testes was investigated in vivo and in vitro in 21 infertile men. Plasma testosterone was determined before and after 3 days of hCG stimulation. Testicular tissue obtained by bilateral biopsies was subjected to (1) histological examination, (2) determination of basal testosterone concentration and (3) incubation with hCG. Patients were grouped according to histology. In vitro basal and stimulated testicular testosterone was similar in patients with normal histology, Sertoli-cell-only syndrome and spermatogenic arrest. Tissue from patients with Leydig cell hyperplasia showed 3-fold higher basal testosterone levels and a greater response to hCG. All patients had plasma testosterone levels and responses to hCG in the normal range. There was no significant correlation between the data obtained in vivo and in vitro, indicating that testosterone determinations in peripheral blood do not necessarily reflect the intratesticular situation. There was no evidence for gross abnormality in Leydig cell function accompanying disturbed spermatogenesis.
BIOLOGICALLY ACTIVE LUTEINIZING HORMONE (LH) IN PLASMA
Authors: Rajalakshmi M. , Robertson D. M. , Choi S. K. , Diczfalusy E. 
Published: December 2008

ABSTRACT
An in vitro bioassay method for measuring LH activity was applied to male plasma. This method is based on the specific testosterone response to LH activity by interstitial cells from mouse testes. In contrast to assays conducted on female plasma, non-parallel response lines were obtained between serial dilutions of untreated male plasma and the International Reference Preparation for Human Pituitary Gonadotrophins (FSH and LH/ICSH) for bioassay (code no. 69/104). In an attempt to eliminate this source of error, which would invalidate the assays, plasma was subjected to either ether extraction or charcoal adsorption prior to assay. While ether extraction was ineffective, charcoal treatment eliminated the source of non-parallelism. Evidence is presented indicating that the inclusion of a charcoal pre-treatment step provides an assay method for LH which fulfils the recognized criteria of reliability when applied to male plasma.
An investigation of the likely causes of non-parallelism was undertaken by incubating mouse interstitial cells with various steroids and steroid sulphates at concentrations likely to be present in plasma. While most of the presumed precursors of testosterone were converted to testosterone, steroid sulphates (dehydroepiandrosterone sulphate and pregnenolone sulphate) at high concentrations as present in male plasma were the most active compounds in forming testosterone. However, the amount of testosterone produced from these precursors under controlled conditions was insufficient to account entirely for the deviation from parallelism observed with male plasma. Hence, the non-parallelism observed with untreated plasma samples cannot be entirely explained by the presence of steroidal testosterone precursors in male plasma.
REDUCED UPTAKE OF OESTRONE AND CORTICOSTERONE BY CELLS FROM CIRRHOTIC RAT LIVER
Authors: Rao Marie Luise , Rao Govind S. , Höller Michael , Breuer Heinz 
Published: December 2008

ABSTRACT
The uptake of oestrone and corticosterone into isolated parenchymal cells from normal and cirrhotic rat livers has been studied. The maximal uptake of both hormones by cells from cirrhotic livers was reduced by 30 to 50 % compared to the uptake by normal cells. The affinity of the uptake systems for both hormones was similar in cells from normal and cirrhotic livers.
The activation energy for the uptake of oestrone by normal cells was 3.9 ± 0.2 kcal./mol from 0 to 40°C, whereas that for the uptake of oestrone by cells from cirrhotic rats was 3.0 ± 0.1 kcal./mol. Glucuronidation of oestrone by cells from cirrhotic livers was lower than that by cells from normal livers, but that by homogenates of the diseased tissue was not affected.
The Arrhenius plot of the uptake of corticosterone by normal cells showed a transition at 17°C; the activation energy for the uptake by normal cells was 16.0 ± 1.4 and 6.0 ± 0.7 kcal./mol from 0 to 17°C and 17 to 40°C, respectively. The activation energy for the uptake of corticosterone by cells from cirrhotic livers was 11.4 ±0.6 and 2.8 ± 0.2 kcal./mol from 0 to 17°C and 17 to 40°C, respectively. Sulfhydryl reagents reduced the uptake of both hormones by both cell preparations by 10 to 20 %; treatment of cells with β-galactosidase, phospholipase A and pronase reduced the uptake of both hormones. The results suggest that the amount of oestrone and corticosterone transported into isolated parenchymal cells from cirrhotic livers is decreased.
HIGH CORTICOSTEROID LEVELS IN PLASMA OF ADULT AND FOETAL WEDDELL SEALS (LEPTONYCHOTES WEDDELLI)
Authors: Liggins G. C. , France J. T. , Knox B. S. , Zapol W. M. 
Published: December 2008

ABSTRACT
Pregnant and non-pregnant Weddell seals and foetuses were found to have very high plasma concentrations of corticosteroids (1–7 μmol/l) that were unaffected by stress. Cortisol comprised most of the corticosteroid in the adult but only 50 % of that in the foetus. The affinity constant (4.30–5.53 × 107 l/mol) and specificity of CBG and the MCR (4.5 l/d/kg lean body mass) in adult seals were similar to those of Man. The binding capacity of CBG (1.48–1.86 μmol/l) which is approximately three times that of Man contributed to the high plasma corticosteroid concentrations but the main factor was the cortisol turnover rate of 3670 μmol/d (1.3 g/d) which is the highest value reported in any species.
PROGESTERONE-INDEPENDENT AVIDIN INDUCTION IN CHICK TISSUES CAUSED BY TISSUE INJURY AND INFLAMMATION
Authors: Elo Heikki A. , Kulomaa Markku S. , Tuohimaa Pentti J. 
Published: December 2008

ABSTRACT
Progesterone was administered to oestrogen-treated and untreated chicks, or inflammation in the abdominal cavity was caused by intestine and liver injury or intraperitoneal actinomycin D administration. Local injury to the pectoral muscle was also carried out. Chicks were killed 24–26 h after the treatment and the biotin-binding egg white protein, avidin, was assayed in a number of tissues using a [14C] biotin-binding method and radioimmunoassay. Ovalbumin was also assayed with a radioimmunoassay. Avidin was not found in the tissues of control chicks. Progesterone induced avidin only in the oviducts of oestrogen-treated chicks. After intestine and liver injury avidin was found, however, in all the tissues of oestrogen-treated and untreated chicks studied except for the brain. The concentrations were highest in the oviduct, lung, intestine and bursa of Fabricius. Actinomycin D (200 μg/kg) caused ascites and subcutaneous oedema in 40–60 % of the chicks, and avidin was found only in the tissues of these inflamed animals. Avidin production caused by the local muscular injury was restricted to the injured area. Tissue injury and inflammation did not induce ovalbumin in any tissue.
The study shows that avidin can be induced besides the oviduct also in non-oviductal chick tissues, and it is proposed that there are both progesterone-dependent and -independent avidin induction mechanisms.
EVALUATION OF THE GONADOTROPHIC RESPONSIVENESS OF THE PITUITARY TO ACUTE AND PROLONGED ADMINISTRATION OF LH/FSH-RELEASING HORMONE (LH-RH) IN NORMAL FEMALES AND MALES
Authors: Pinto Heidi , Wajchenberg Bernardo Leo , Lima Fabio Bessa , Goldman Jayme , Comaru-Schally Ana Maria , Schally Andrew V. 
Published: December 2008

ABSTRACT
In normal females, the injection of 25 μg of LH-RH (acute test) induced a greater LH and FSH release from the pituitary in the mid-luteal than in the mid-follicular phase of the menstrual cycle. In normal males, the responsiveness to 25 μg LH-RH was greater than that in females at mid-follicular but not at the luteal stage. The pituitary response to the prolonged LH-RH infusion (0.21 μg/min/8 h) was similar in both phases of the cycle of the females with a decline in serum gonadotrophins after the 4th hour and was paralleled by a significant increase of plasma oestradiol levels. In males the LH, but not the FSH secretion was lower as compared to female subjects, and gonadotrophin levels did not show a fall during the infusion. The acute injection of 25 μg LH-RH at the end of a prolonged infusion induced the same response in the female subjects in both phases of the cycle. In males, the acute test following prolonged infusion produced a similar LH secretion, but a lower FSH response than in females. The comparison of the acute test alone and that preceded by a prolonged LH-RH infusion, demonstrated that, in females, the only significant differences consisted of a greater LH secretion in the former test in the mid-luteal phase. In males there was greater FSH secretion in the acute isolated test than when this test was given after the prolonged infusion.
GROWTH IMPAIRMENT WITH ELEVATED SOMATOMEDIN LEVELS IN CHILDREN WITH CHRONIC RENAL INSUFFICIENCY
Authors: Spencer E. Martin , Uthne K. O. , Arnold W. C. 
Published: December 2008

ABSTRACT
In children with chronic renal insufficiency serum levels of somatomedin measured by radioreceptor assay were found to be strikingly elevated and were in the same range as in acromegaly in spite of decreased growth. The serum somatomedin level was inversely correlated with renal function and children on haemodialysis had the highest values. The elevated somatomedin was most likely due to progressive destruction of the kidney, the primary catabolic site for somatomedin and other polypeptides. After successful transplantation the somatomedin values fell to slightly above normal even though growth was still impaired. Using a bioassay based on the mitogenic property of somatomedin, a lower than normal rather than an increased level was found in chronic renal insufficiency suggesting that in uraemia an inhibitor to somatomedin bioactivity was present. It is concluded that the cause of the growth failure in chronic renal insufficiency and after transplantation is not due to a lack of somatomedin, but an inhibitor to its action could be a factor. It would appear that a normal somatomedin may be necessary for normal growth, but it is not sufficient.
TRANSDUCER PROBE FOR THE MEASUREMENT OF OESTRADIOL-INDUCED CHANGES IN THE VAGINA OF OVARIECTOMIZED EWES
Authors: Borth Rudi , Benoit Henry J. , Woolever C. Allan 
Published: December 2008

ABSTRACT
A modified non-invasive vaginal probe, using electronic transducers to monitor six physical variables reflecting vaginal changes, was tested in oophorectomized ewes according to a Latin-Square design allocating six treatments to six animals in a balanced time sequence. The transducers measured thermal conductance, temperature near the cervix and near the vulva, and light reflectance at 900, 660, and 565 nm. The treatments included four iv doses of oestradiol-17β (0.5, 5.0, 50, and 500 μg per 50 kg body weight) and two controls (injection vehicle, and no injection). Despite large residual variation, the results (1) show that the higher oestradiol doses produced responses of all six variables; (2) suggest improvements in future probe design; and (3) raise interesting questions on dose-response relationships deserving further study.
ENDOCRINE STUDIES AND SUCCESSFUL TREATMENT IN A PATIENT WITH TRUE HERMAPHRODITISM
Authors: Valdés Evangelina , Fernández del Castillo Carlos , Gutiérrez Raul , Larrea Fernando , Medina Martha , Pérez-Palacios Gregorio 
Published: December 2008

ABSTRACT
A 12-year old, 46 XX true hermaphrodite born with genital ambiguity was studied and successfully treated. The serum LH and FSH profile resembled that of a pubertal normal individual, and LH-RH administration induced a normal LH response. Baseline testosterone serum levels were within the range for normal children. Exogenous HCG stimulation induced a significant serum testosterone increase up to values similar to those observed in normal post-pubertal males. Surgical examination disclosed the presence of bilateral ovotestis, normal Mullerian derivatives, epididymis, and vas deferens. A complete ovotestis with testicular predominance and the testicular portion of the contralateral ovotestis as well as the Wolffian derivatives, were removed. A further HCG stimulation 3 months after surgery, failed to induce serum testosterone increase. Spontaneous menarche was observed 6 months after surgery and ovulation was well documented. At present the patient has several characteristics of female sex including those of chromosome complement, gonad, internal and external genitalia, hormone levels and gender identity, thus demonstrating that treatment was successful and that reproductive function could be obtained. The finding of spontaneous ovulation following removal of the testicular portion suggests normal cyclic gonadotrophic release implying a difference between animal models and man in regard to hypothalamic virilization.