bluuebunny/crossref_metadata_2025_split huggingface dataset:
OVARIAN STEROID EFFECTS ON GONADOTROPHIN OUTPUT, AND ON THE INCORPORATION OF 35S FROM METHIONINE INTO PROTEIN OF DISCRETE BRAIN AREAS AND THE ANTERIOR PITUITARY
Authors: ter Haar M. B. , MacKinnon P. C. B. 
Published: December 2008

ABSTRACT
The effects of various ovarian hormones administered on the morning of pro-oestrus on gonadotrophin levels and the incorporation of 35S from methionine into protein of discrete areas of the brain and the anterior pituitary were investigated at 15.00 h of the same day in female rats. The hormones which were investigated in this study could be divided in general into two groups according to their actions. The first group, consisting of oestradiol-17β and progesterone, tended to advance the preovulatory surge of luteinizing hormone (LH) by 3–6 h from 18.00–21.00 h, together with the peaks of [35S] incorporation in the median eminence area and the anterior pituitary which normally accompany the LH surge. The second group, consisting of the LH-stimulated reduced progesterone metabolites, 5α-pregnane-3,20-dione (pregnanedione) and 20α-hydroxypregn-4-en-3-one (dihydroprogesterone), tended to inhibit serum gonadotrophin levels as well as inhibiting the pro-oestrous increase of [35S] incorporation in the median eminence area and in the amygdala, but not in the preoptic area and the anterior pituitary.
On the afternoon of pro-oestrus in intact animals, luteinizing hormonereleasing hormone or LH administration had the same effect on [35S]incorporation in the brain as did the progesterone metabolites, though this effect was not observed if the animals had been ovariectomized a few hours beforehand.
It is suggested that certain ovarian hormones are involved in the neural events which induce the pre-ovulatory LH surge, while others are associated with neural events which terminate the stimulus for the LH surge.
SUBCELLULAR FRACTIONATION BY CENTRIFUGATION OF HOMOGENATES OF THE NEURAL LOBE OF THE BOVINE PITUITARY GLAND: IDENTIFICATION OF DIFFERENT POOLS OF HORMONE IN THE HOMOGENATE AND ISOLATION OF NEUROSECRETOSOMES
Authors: Vilhardt Hans , Baker Ruth V. , Hope Derek B. 
Published: December 2008

ABSTRACT
1. Homogenates of bovine pituitary neural lobe tissue were subjected to differential centrifugation. Six subcellular fractions (I-VI) were obtained and the distribution among them of various cell organelles was studied by means of markers. Fraction II (800–3000 gav), the nerve-ending fraction (neurosecretosomes), contained sedimentable lactate dehydrogenase, hormone and a large proportion of the total Mg2++ Na++ K+-ATPase.
2. Lysis of the neurosecretosomes in hypotonic sucrose solutions led to loss of lactate dehydrogenase and vasopressin.
3. Centrifugation of the granule fraction (IV) on a sucrose gradient (1.3–2.0 m sucrose) gave a bimodal distribution of vasopressin. Purified neurosecretory granules were recovered from the denser band. Centrifugation on modified gradients (0.8–2.0 or 0.4–2.0 m sucrose) increased the yield of hormone in the denser band but the purity of the granules was decreased.
4. Considerable purification of the neurosecretosomes (fraction II) was achieved by "washing". Centrifugation of washed neurosecretosomes on sucrose density gradients led to the accumulation of all activities at a region between 1.4 and 1.5 m sucrose.
5. The distribution of Mg2++ Na++ K+-ATPase in centrifugal fractions indicated that the neurosecretosomes had been isolated in relatively high yield.
SERUM THYROXINE-BINDING GLOBULIN: DETERMINATION BY COMPETITIVE LIGAND-BINDING ASSAY IN THYROID DISEASE AND PREGNANCY
Authors: Mulaisho C. , Utiger R. D. 
Published: December 2008

ABSTRACT
Serum thyroxine-binding globulin (TBG) concentrations were measured by competitive ligand-binding assay in normal subjects and patients with a variety of abnormalities of thyroid hormone production or TBG production. The mean serum TBG concentration in 73 normal adults was 3.4 ± 0.6 mg/100 ml. No correlations with age, sex or serum thyroxine (T4) or triiodothyronine (T3) concentrations were found. Serum TBG concentrations were normal in patients with hyperthyroidism. They were significantly elevated in hypothyroid patients, and fell to normal with thyroxine treatment. In pregnant women, serum TBG concentrations were markedly increased, being 7.1 ± 1.2 (mean ± sd) mg/100 ml in women in their first trimester, 9.0 ± 1.0 mg/100 ml in the second trimester and 8.9 ± 1.6 mg/100 ml in the third trimester. There was a positive correlation between serum TBG concentration and both serum T4 and serum T3 concentrations in pregnant women. Competitive ligand-binding assay is a simple and reliable method for TBG assay and yields results similar to those of electrophoretic saturation techniques.
ENDEMIC GOITRE IN ALTO ADIGE (ITALY)
Authors: Platzer S. , Fill H. , Riccabona G. , Glatzl J. , Seidl J. , Cenderelli G. , Migliardi M. , Varetto H. , Costa A. 
Published: December 2008

ABSTRACT
The whole population of Certosa (Karthaus) (altitude 1327 m), a little village in the Alto Adige province in Northern Italy, was studied regarding the incidence and pathophysiological data of endemic goitre. The study included 204 subjects: in 85 % of the whole population, and in 48 % of the school-children population from 6-14 years of age, thyroid enlargement and/or nodularity was found. The 24 h [131I]uptake was 48.6 ± 11.96; the grade "O" thyroids also showed an increased uptake. The region is poor in iodine; the mean iodine content of 55 samples of local drinking water was 0.81 ± 0.96 μg/I; the iodine content of several foodstuffs was definitely lower than those from Turin's markets. The mean iodine excretion in 60 samples of urine was 35.96 ± 22.4 μg/g creatinine. Urinary iodine excretion showed a linear negative correlation with [131I]uptake and did not correlate well with the presence or size of the goitre.
The mean values of PBI (6.12 ± 1.57 μg/100 ml) of T4 (7 ± 2.3 μg/100 ml), of T3 (121 ± 55.4 ng/100 ml) and of a free thyroxine index (ETR = 0.95), as well as of TSH (2.63 ± 1.9 μU/ml) were in the normal range. Grade III goitres had slightly lower hormonal values, and a somewhat elevated T3/(T4x100) ratio (0.19). Serum TSH levels showed no correlation with the presence or size of the goitre, radioiodine uptake, the urinary iodine excretion, and not always showed an inverse correlation with the peripheral thyroid hormone values. Urinary thiocyanate excretion (mean value 9.28 ± 2.96 mg/24 h) did not show any relation to the presence of goitre.
Raven's tests and physical data obtained from school-children in Alto Adige show some slight alteration in the distribution pattern when compared to normal populations.
It is concluded that iodine deficiency exists in the studied area, but that it is not always associated with goitre, and that other pathological factors must be involved in goitrogenesis. Goitre is not coupled with enhanced TSH serum levels.
The slight alteration in intellectual and somatic development in schoolchildren may possibly be related to iodine deficiency; other environmental or genetic factors, however, cannot be excluded.
C-PEPTIDE IN DIABETIC CHILDREN AFTER STIMULATOIN WITH CLUCAGON COMPARED WITH FASTING C-PEPTIDE LEVELS IN NON-DIABETIC CHILDREN
Authors: Ludvigsson J. , Heding L. G. 
Published: December 2008

ABSTRACT
Fasting serum C-peptide and total immunoreactive insulin (IRI) were determined in 38 non-diabetic children and adolescents 6–22 years old. C-peptide varied between 0.22–0.73 pmol/ml (mean ± sd, 0.45 ± 0.11). There was a tendency to higher values during puberty. No difference was found between subjects with or without a family history for diabetes. IRI varied between 0–31 μU/ml (mean ± sd, 11.3 ± 6.5).
The C-peptide response to glucagon was studied in 10 insulin dependent juvenile diabetics 11–19 years old, who had had measurable amounts of fasting C-peptide on some occasions during the previous years. Duration of diabetes varied between 4–12 years. A slight but significant rise in C-peptide level occurred in 3 patients. Their metabolic control estimated on the basis of daily urinalysis was "excellent" or "good". The results support the hypothesis that even trace remnants of the beta cell function may be of importance for the metabolic control in juvenile diabetes.
STUDIES ON THE MECHANISMS OF SOMATOSTATIN ACTION ON INSULIN RELEASE
Authors: Claro A , Grill V. , Efendić S. , Luft R. 
Published: December 2008

ABSTRACT
The effects of somatostatin on insulin release and cyclic AMP metabolism were studied in collagenase-isolated islets of Langerhans from the rat. Concentrations from 500 to 2000 ng/ml significantly inhibited glucose stimulated insulin release, while 100 and 200 ng/ml were ineffective. Somatostatin (2000 ng/ml) inhibited insulin release and [3H]-cyclic AMP accumulation induced by 16.7 mm glucose after 10 and 30 min of incubation. In dose-response studies, the inhibition by somatostatin of the effect of glucose on [3H] cyclic AMP and insulin release could be overcome by a high concentration of the hexose (44.9 mM), suggesting competitive inhibition. In the absence of glucose, somatostatin inhibited [3H] cyclic AMP accumulation induced by the phosphodiesterase inhibitor, IBMX, while no inhibition was seen, again in the absence of hexose, when the [3H] cyclic AMP levels had been raised by the adenyl cyclase stimulator, cholera toxin. Somatostatin did not affect phosphodiesterase activity when added to islet homogenates, but preincubation of the islets with the peptide before homogenization decreased the activity by about 30 %.
It is suggested that somatostatin-induced inhibition of insulin release is, at least partially, mediated by cyclic AMP, probably through an action on islet adenyl cyclase.
STUDY OF THE EFFECT OF OESTRADIOL ON HEXOSAMINE-CONTAINING SUBSTANCES AND A POSSIBLE RECEPTOR IN THE SKIN OF MALE MICE
Authors: Kanke Y. , Nishina H. , Mori Y. , Bashey R. I. 
Published: December 2008

ABSTRACT
Male mice were treated with 10 μg of oestradiol for 5 days in order to study the effect of the hormone on both the distribution and the rate of synthesis of glycosaminoglycans and glycoproteins in the skin. Oestradiol exerts a very specific effect on glycosaminoglycans by increasing hyaluronic acid concentration more than 11 times. Effects on other hexosaminecontaining substances were much smaller and less consistent. Although the above increase of hyaluronic acid was due mainly to an augmentation of its synthesis, the results also indicate the possibility of a blockage in the breakdown process. Despite the fact that oestrogen produces such large changes, a specific cytosol receptor of the hormone was not discerned and it was concluded that male mouse skin is not an oestrogen receptor tissue in the classical sense.
CONGENITAL GENERALIZED LIPODYSTROPHY AND EXPERIMENTAL LIPOATROPHIC DIABETES IN RABBITS TREATED SUCCESSFULLY WITH FENFLURAMINE
Authors: Trygstad Olav , Foss Irene 
Published: December 2008

ABSTRACT
Lipoatrophic diabetes has been produced in rabbits by injection of a fraction prepared from the urine from patients with congenital generalized lipodystrophy. Both these conditions are considered to be hypothalamic syndromes. The animals, and a patient with congenital generalized lipodystrophy and latent diabetes were treated with the dopamine receptor blocker, pimozide, for 4 and 17 months, respectively. The results were discouraging even though the patient got a daily dose of 16 mg pimozide. Fenfluramine has a lowering effect on brain serotonin, and peripheral effects on glucose and triglyceride metabolism. This drug improved the general condition of the rabbits with lipoatrophic diabetes, as well as that of the patient with congenital generalized lipodystrophy. The rabbits became normoglycaemic and insulin sensitive. In the patient a normalization of the urinary excretion of the serotonin metabolite 5-OH-indole acetic acid was observed.
His voracious hunger and profuse perspiration were reduced, the hyperkeratotic layer of the skin peeled off, and the pigmentations of the skin decreased. There was observed an improvement of ALAT and ASAT, normalization of the fasting blood glucose, and increased sensitivity to exogenous insulin. After 11 months of 200 mg fenfluramine daily addtitional administration of 2 g clofibrate per day produced normalization of the serum triglyceride concentration and a marked reduction of the resistance to insulin. Three more patients with congenital generalized lipodystrophy, two of whom have manifest diabetes, have now started treatment with fenfluramine and are improving. The rabbits got relapse of their lipoatrophic diabetes when the fenfluramine treatment was stopped. It is suggested that a disturbance in the serotonin metabolism of the central nervous system may be of pathogenetic importance in congenital generalized lipodystrophy.
EFFECT OF THYROTROPHIN RELEASING HORMONE (TRH) IN PATIENTS WITH PITUITARY DISORDERS
Authors: Lindholm J. , Dige-Petersen H. , Hummer L. , Rasmussen P. , Korsgaard O. 
Published: December 2008

ABSTRACT
The secretion and biological activity of thyroid stimulating hormone (TSH) were studied in 22 patients with a pituitary tumour (17 acromegalics and 5 patients with a chromophobe adenoma) and in 36 hypophysectomized patients (16 acromegalics and 20 with a chromophobe adenoma). Thyroid function was assessed by serum thyroxine (T4), serum triiodothyronine (T3), and thyroxine-binding globulin (TBG) concentration. Serum TSH was measured before and after injection of TSH releasing hormone (TRH), and in 19 hypophysectomized patients the T3 response after TRH was measured. In addition a TRH test was performed 1–2 weeks after surgery in 11 patients.
The basal serum TSH did not differ from euthyroid control values in any of the groups and no late effect of hypophysectomy was observed. Subnormal peak TSH values were seen in 10 out of 37 euthyroid patients, whereas 9 out of 11 hypothyroid patients responded normally. Hypophysectomy caused an immediate but transient decrease in peak TSH in patients with a chromophobe adenoma only. The rise in serum T3 after TRH was significantly lower in hypophysectomized patients than in controls. An increase in TSH was followed by a T3 response in all patients except in 4 out of 8 euthyroid acromegalics. In patients operated on for a chromophobe adenoma the T3 response was correlated with serum T4, whereas this was not the case in acromegalics.
INTRAVENOUS AND PERORAL TRH STIMULATION IN SPORADIC ATOXIC GOITRE
Authors: Kirkegaard C. , Faber J. , Friis T. , Lauridsen U. Birk , Rogowski P. , Siersbœk-Nielsen K. 
Published: December 2008

ABSTRACT
Thyrotrophin releasing hormone (TRH) stimulation test with 200 μg iv was performed in 35 patients with atoxic sporadic goitre. In 23 patients with diffuse goitre 7 showed a lack of increase in serum thyrotrophin (TSH) at a significantly increased frequency compared to controls (P = 0.0028). In 4 patients with solitary nodules 2 showed no significant response to TRH (negative), while 3 of the 8 patients with multinodular goitres had negative TRH test. Only 6 of the 12 TRH negative patients also had non-suppressible 131I uptake following T3. No significant difference in age and thyroid parameters was found between the TRH negative and TRH positive patients. In 7 TRH negative patients the test was repeated with 400 μg TRH but all remained negative. Five of these patients were given TRH perorally 80 mg daily for 2 weeks resulting in a significant increase in serum T4 and T3. No detectable increase in TSH was found. The response to iv bovine TSH in 4 TRH negative patients was found to be normal, suggesting that there was normal thyroid sensitivity to TSH. Our findings suggest that patients with TRH negative atoxic goitre can release biological active TSH following prolonged TRH stimulation. The high frequency of a negative standard TRH test in atoxic goitre seems to diminish the diagnostic value of the standard TRH test.
STIMULATION OF PERIPHERAL T3 FORMATION BY ORAL BUT NOT BY INTRAVENOUS GLUCOSE ADMINISTRATION IN FASTED SUBJECTS
Authors: Westgren U. , Ahrén B. , Burger A. , Melander A. 
Published: December 2008

ABSTRACT
Fasting is known to promote a shift in the conversion of thyroxine (T4), more being deiodinated to an inactive form, reverse triiodothyronine (rT3), and less to active triiodothyronine (T3). The mechanism behind this change is not known, but it has recently been demonstrated that the proportion of dietary carbohydrates influences the serum concentration of T3 and rT3. Therefore, it is possible that the deiodination of T4 is subordinated to gastroenterohepatic regulation.
To explore this possibility, we administrated glucose by the oral or the intravenous route to volunteers, who had been fasted for 48 h. It was found that glucose normalized the low fasting T3 concentrations only after oral administration. This supports the assumption that some gastro-enterohepatic factor participates in the regulation of T3 formation.
THE EFFECT OF CALCIUM AND DIBUTYRYL-cAMP ON THE SECRETION OF PARATHYROID HORMONE BY HUMAN PARATHYROID ADENOMAS IN ORGAN CULTURE
Authors: Dietel M. , Dorn G. , Montz R. , Altenähr E. 
Published: December 2008

ABSTRACT
The effect of different calcium concentrations as well as dibutyryl-cyclic adenosine 3′,5′-monophosphate (DB-cAMP) on the secretion of parathyroid hormone by human parathyroid adenomas taken from patients with primary hyperparathyroidism (pHPT) was studied in organ culture. Their influence on the release of hormone was determined. The tissue was incubated in culture medium for 4 h; the medium was changed hourly and analyzed for immunoreactive parathyroid hormone (PTH) by radioimmunoassay.
The hormone secretion showed an inverse relationship to different calcium concentrations in the medium and could be stimulated independently of the calcium concentration by adding DB-cAMP.
These results suggest that the examined parathyroid adenomas are sensitive to physiological stimuli.
CHARACTERIZATION OF HUMAN OVARIAN OESTRADIOL-17β OXIDOREDUCTASE ACTIVITY
Authors: Pittaway Donald E. , Andersen Richard N. , Givens James R. 
Published: December 2008

ABSTRACT
Oestradiol-17β oxidoreductase activity, which catalyzes the interconversion of oestrone and oestradiol, was investigated in preparations of human ovaries. The enzyme activities were localized primarily in the 105 000 × g supernatant fraction; dialyzed supernatant preparations were used in subsequent studies. The pH optima were 6.9 for reduction and 8.1 for 17β-dehydrogenation. The apparent Michaelis constants for oestrone and oestradiol were 1 × 10-7 m and 5 × 10-7 m, respectively. The enzyme activity was present with either NADP(H) or NAD(H), though NADP(H) were the preferred cofactors. Non-aromatic steroids androstenedione, dehydroepiandrosterone, testosterone and 5-androstene-3β,17β-diol were poor substrates for the enzyme preparation. Methylation of the phenolic hydroxyl of oestrone and oestradiol resulted in slightly enhanced activities. The sulfhydryl reagent, N-ethylmaleimide, inhibited the reduction of oestrone. A dialyzed supernatant preparation retained approximately 79 % of the original enzyme activity when stored at −20°C for 6 weeks.
THE STIMULATION OF PROLACTIN SECRETION BY SULPIRIDE IN "ADOLESCENT GYNAECOMASTIA"
Authors: D'Agata R. , Andó S. , Gulizia S. , Condorelli L. , Paci C. , Scapagnini U. , Polosa P. 
Published: December 2008

ABSTRACT
In order to evaluate the function of the hypothalamic-pituitary-prolactin axis in "adolescent gynaecomastia" (AG), sulpiride was administered to 7 normal boys and 7 boys with AG. The maximum increase in serum prolactin (PRL) above the mean baseline level (Δmax) was used as index of response. The sulpiride induced a greater PRL release in boys with gynaecomastia than in the controls.
Our data indicate that boys with gynaecomastia may have a greater pituitary prolactin pool. The results also illustrate the usefulness of specific neurotrophic agents such as sulpiride as important tools for evaluating the function of the hypothalamic-pituitary-PRL axis.
HIGH MOLECULAR THYROTROPHIN ("BIG"-TSH) FROM HUMAN PITUITARIES: PREPARATION AND PARTIAL CHARACTERIZATION
Authors: Erhardt Friedrich W. , Scriba Peter C. 
Published: December 2008

ABSTRACT
Homogenates of human pituitaries were centrifuged at 30 000 × g and the supernatant chromatographed on Sephadex G-100. Approximately 1 % of the radioimmunologically measured total activity of TSH was eluted in the void volume. Rechromatography of this material on Sephadex G-200 usually showed TSH-activity at Kav = 0.5 (regular TSH), Kav = 0 (void volume-TSH) and at Kav = 0.3 ("big"-TSH). "Big"-TSH was extracted from the corresponding fractions by affinity-chromatography with solid phase anti-TSH. It was eluted with 5 mol/l ammonium thiocyanate and further characterized:
1. The molecular weight was approximately 200 000 by comparison with bovine catalase on Sephadex G-200.
2. Immunoidentity as compared with standard-TSH (M. R. C. 68/38) was shown by parallel dilution curves in the radioimmunoassay.
3. Concanavalin-A-Sepharose adsorbed "big"-TSH, which could be eluted with α-methyl-D-mannoside, indicating the glycoprotein nature of "big"-TSH.
4. On polyacrylamide-gel-electrophoresis pH 7.5, "big"-TSH migrated faster (RF = 0.32) than regular TSH (RF = 0.1), indicating a more negatively charged molecule.
5. "Big"-TSH, in contrast to regular TSH, was remarkably stable against 6 mol/l guanidine hydrochloride, suggesting a covalently linked (aggregate) structure.
6. 1 % mercaptoethanol destroyed the immunological activity of both regular and "big"-TSH.
7. "Big"-TSH was digested by trypsin, under mild conditions, to radioimmunologically active products with molecular weights between "big"- and regular TSH, but practically no regular TSH was formed.
8. "Big"-TSH and guanidine-treated "big"-TSH, as well as regular TSH and TSH from the void volume of Sephadex G-200 columns, exhibited biological activity in a cytochemical bioassay in good agreement with the respective immunological activities.
THE EFFECT OF LUTEINIZING HORMONE-RELEASING HORMONE AND STEROIDS ON THE RELEASE OF LH AND FSH FROM INCUBATED TURKEY PITUITARY CELLS
Authors: Godden Patricia M. M. , Luck M. R. , Scanes C. G. 
Published: December 2008

ABSTRACT
The secretion of immunoreactive luteinizing hormone (IR-LH) and follicle stimulating hormone (IR-FSH) by turkey pituitary cell suspensions has been investigated. No significant effects of synthetic ovine luteinizing hormone-releasing hormone (LH-RH) on gonadotrophin release were found with cells from 17 to 19 week old birds, though IR-LH secretion was elevated with tissue from young (13 weeks) birds. Although IR-FSH secretion was increased in the presence of progesterone alone, effects of oestradiol and testosterone on IR-FSH release and of oestradiol, progesterone and testosterone on LH-RH release were observed when the steroid treatment was combined with that of LH-RH.
HOMOLOGOUS RADIOIMMUNOASSAY FOR CANINE PROLACTIN
Authors: Knight P. J. , Hamilton J. M. , Scanes C. G. 
Published: December 2008

ABSTRACT
A homologous double antibody radioimmunoassay has been developed for canine prolactin. Purified canine prolactin was iodinated by lactoperoxidase/H2O2 to an average of 101 ± 10.1 μCi/μg. Antiserum was used at a final dilution of 1:80 000 and at this concentration bound approximately 20% of the added tracer in the absence of competing unlabelled prolactin. Partial cross-reaction was observed with ovine and bovine prolactin but there was no cross-reaction with a highly purified canine growth hormone preparation. Dilutions of pregnant and lactating bitch sera were parallel to the purified canine prolactin standard curve. Mean prolactin levels in normal male and anoestrous females were 8.8 ± 0.8 and 12.6 ± 2.6 ng/ml, respectively. Thyrotrophin-releasing hormone (TRH) induced a consistent elevation in prolactin levels 15–30 min after intravenous injection.