bluuebunny/crossref_metadata_2025 huggingface dataset:
FEEDBACK CONTROL OF FSH IN THE MALE: ROLE OF OESTROGEN
Authors: Walsh Patrick C. , Swerdloff Ronald S. , Odell William D.
Published: December 2008

Serum follicle stimulating hormone (FSH) and luteinizing hormone (LH) were measured by radioimmunoassay in a group of elderly men following castration and oestrogen therapy. Prior to orchiectomy, mean serum concentrations of LH and FSH were within the normal range. Two days following castration, serum LH concentrations increased in all eight patients; higher levels of LH were subsequently measured in all but one patient after periods of time ranging from 49 to 210 days. Serum FSH levels, measured in three patients following castration, increased in a pattern parallel to LH changes. Ethinyl oestradiol (EOe) in doses ranging from 5 to 300 μg/day was administered to ten men who had been castrated 3 to 72 months earlier. Oestrogen treatment suppressed both LH and FSH in a parellel manner in nine of ten patients. LH was first suppressed to intact levels in one of eight patients treated with 20 μg/day of EOe, in two of six patients treated with 50 μg/day, and in one patient by 80 μg/day. FSH was not suppressed to precastration levels until 50 μg/day of EOe was administered; this dose suppressed three of six patients. Higher doses of EOe (150–300 μg/day) suppressed both LH and FSH to levels below the sensitivity of the assay. These data fail to demonstrate any differential effect of oestrogen on LH and FSH release.
IODINATED THYROLIPIDS: THEIR POSSIBLE ROLE IN HORMONOGENESIS
Authors: Shah D. H. , Thakare U. R. , Shownkeen R. C. , Pahuja D. N. , Mandlik M. Y.
Published: December 2008

A total of 42 human thyroid glands (nodular goitre 9, adenoma with cystic degeneration 6; toxic goitre 10; carcinoma 14; and normal thyroid gland 3) were examined in vitro for iodination of an unidentified polar non-phosphatide lipid fraction (fraction II). The radioiodine incorporation in fraction II was 49.3 %, 43.6 %, 32.8 %, 20.7 %, and 22.0 % respectively in normal, nodular goitre, adenoma with cystic degeneration, toxic goitre and thyroid carcinoma.

In vitro studies with surviving sheep thyroid slices did not show any relation between the iodination of fraction II and thyroxine formation over a period of 120 min.

However, a highly significant correlation (r-value= 0.96375) was observed between the iodination of fraction II and thyroxine formation in vivo in the rat thyroid gland over a period of 24 h.

We have previously postulated that iodination of fraction II may be interrelated to thyroxine formation. In the light of this hypothesis and the above results we suggest that the iodination of fraction II and thyroxine formation in the thyroid gland may be interrelated, the degree of iodination of fraction II being modulated by the amount of thyroxine formed within the thyroid gland.
IN VIVO AND IN VITRO STUDIES ON IONIZED VERSUS TOTAL SERUM CALCIUM IN HYPERPARATHYROIDISM
Authors: Lindgärde F.
Published: December 2008

Measurements of ionized (Ca+ + ) calcium and total (Cat) calcium have been performed in sera from hyperparathyroid, parathyroidectomized and control subjects. The relationship between Ca++ and Cat has been analysed statistically. It was found that two straight lines with the point of intersection at Ca++ =2.75 and Cat = 5.55 mEq./l, and slopes of 0.628 and 0.447, respectively, would describe the data more accurately than one single line. However, when the calcium level was varied by the addition of calcium chloride in vitro in individual or pooled sera, the Ca++–Cat relationship appeared to be linear. The results suggest that sera from hyperparathyroid subjects have an increased calcium binding capacity.
A NEW PRINCIPLE FOR THE COMPARISON OF INSULIN SECRETORY RESPONSES
Authors: Johansen Klaus
Published: December 2008

A new principle for the comparison of insulin secretory response has been devised. It consists in the selection of groups of subjects with identical glucose tolerance when subjected to the same amount of oral and intravenous glucose and of intravenous tolbutamide. In this way the problems and assumptions inherent in the use of the insulin/glucose ratio and the administration of different amount of insulin secretagogues have been avoided.

Using this new method of comparison of insulin secretory responses it has been demonstrated that young people maintain the same blood glucose level after stimulation with much smaller plasma insulin levels than their older counterparts, i. e. young non-diabetic and diabetic subjects seem to be more 'sensitive' to endogenous insulin than the old, alternately the old subjects are more 'resistant' to endogenous insulin than young subjects.
PLASMA CONCENTRATION AND PROTEIN BINDING OF OESTRIOL AND ITS CONJUGATES IN PREGNANCY
Authors: Goebelsmann U. , Chen L.-C. , Saga M. , Nakamura R. M. , Jaffe R. B.
Published: December 2008

Oestriol (OE3), oestriol-3-sulphate-16-glucosiduronate (OE3-3S,16Gl), oestriol-3-glucosiduronate (OE3-3Gl), oestriol-16-glucosiduronate (OE316Gl) and oestriol-3-sulphate (OE3-3S) concentrations were measured in a pool of plasma collected from 38 healthy pregnant women at 32 to 36 weeks of gestation. Using tritiated internal standards, OE3 and its 4 conjugates were isolated by countercurrent distributions and, following enzyme hydrolysis and chromatography, quantitated by fluorometry: OE3=1.48 μg/100 ml (13.8%), OE3-3S,16Gl = 3.78 μg/100 ml (35.2%), OE3-3Gl3-3Gl = 1.09 μg/100 ml (10.2%), OE3-16Gl= 1.59 μg/100 ml (14.8%) and OE3-3S = 2.79 μg/100 ml (26%).

OE3 and its conjugates were found to bind to serum proteins in Sephadex G-25 gel filtration and equilibrium dialysis studies. Considerably more OE3-3S and OE3-3S,16Gl than unconjugated OE3, and particularly OE3-16Gl and OE3-3Gl was bound at corresponding serum protein concentrations. When serum was fractionated by starch block electrophoresis and gel filtration on Sephadex G-200, OE3 conjugates were found to be bound by protein(s) present in the albumin fraction.

The difference in plasma protein binding between OE3-3S/OE3-3S,16Gl and OE3-16Gl/OE3-3Gl explains, in part, the preponderance of OE3 sulphoconjugates in plasma and their paucity in urine, as well as the rapid renal excretion of OE3-16Gl and OE3-3Gl. Protein binding thus appears to play an important role in OE3 conjugate transport, metabolism and excretion.
THE ULTRASTRUCTURE OF THE ACCESSORY SEX ORGANS OF THE MALE RAT
Authors: Dahl Erik , Tveter Kjell J. , Kjaerheim Åsmund
Published: December 2008

The present paper describes the fine structure of the accessory sex organs of the male rat as seen after stimulation with testosterone administered to castrated adults as well as infantile rats.

Electron microscopic examination of the testosterone-treated castrated animals revealed an almost complete regeneration of the epithelial cells in all the organs, with a well developed Golgi area, a well developed rough endoplasmic reticulum and an increased number of secretory granules. The results obtained are discussed in relation to the biochemical data, and it is concluded that the various cell types of the accessory genital complex react in a fundamentally similar manner to the administration of testosterone.
IMMUNOCHEMICAL ASSAY OF FOLLICLE-STIMULATING AND LUTEINIZING HORMONE IN THE UNCONCENTRATED URINE OF SUB- OR INFERTILE MALES
Authors: Mauss Joachim , Börsch Gereon
Published: December 2008

The excretion of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) was assayed in unconcentrated 2 × 24 h urine by means of a haemagglutination inhibition reaction FSH-Nosticon and Luteonosticon. The assay was performed in 10 fertile males and 121 sub- or infertile male patients. Normal values were 4.2 (range x̄ ± 2 s: 1.8–9.9) IU/24 h for FSH and 12.9 (5.9–28.2) IU/24 h for LH (by immunoassay, standard: 2nd IRP-HMG). A significant inverse correlation could be established between the log sperm concentration and log FSH excretion (r=−0.68; n= 126; P < 0.001). No correlation could be found between either motility or morphology and log FSH or log LH excretion. In 87 patients with normal testicular size regardless of sperm counts, LH excretion was above the normal range only 6 times. However, in uni- and bilateral testicular atrophy and furthermore in patients with varicocele, the mean LH excretion was significantly elevated in comparison to normal levels.
A SENSITIVE IN VITRO BIOASSAY METHOD FOR LUTEINIZING HORMONE (LH) ACTIVITY
Authors: Van Damme M.-P. , Robertson D. M. , Romaní P. , Diczfalusy E.
Published: December 2008

A specific and sensitive in vitro bioassay method is described for the measurement of LH activity of HCG, HMG and human hypophyseal gonadotrophin (HHG) preparations.

The method is based on the principle that a linear relationship exists between graded doses of HCG, HMG or HHG preparations and the amount of testosterone released into the incubation medium by decapsulated mouse testes.

The sensitivity of the method is 0.4 mIU/ml incubation medium for HCG and 2 mIU/ml for HMG. The useful range of the method is 0.4– mIU/ml for HCG and 2–32 mIU/ml for HMG preparations. A 3 + 3 point design with 6 individual observations per dose is used. Under these experimental conditions the mean index of precision (γ) in 44 assays was 0.22.

All HCG, HMG and HHG preparations yielded parallel dose-effect lines. In the concentrations studied, the assay was not influenced by the presence of FSH, ACTH, STH, LTH, vasopressin, oxytocin and LH releasing hormone activities. The high LH contamination of the highly purified TSH preparations studied precluded an adequate assessment of a possible synergistic or antagonistic effect of TSH on the assay.
REDUCED SENSITIVITY OF THE THYROID TO THYROTROPHIC HORMONE AND LATS FOLLOWING TREATMENT WITH ANTIMICROSOMAL ANTIBODIES
Authors: Földes J. , Takó J. , Bános Cs. , Gesztesi E. , Juhász J.
Published: December 2008

Antibodies raised against the microsomal fraction of the thyroid epithelial cells have been shown to inhibit in vitro binding of LATS to the microsomal fraction and to diminish in vivo thyroid stimulating effects of both LATS and TSH. Antimicrosomal antibody is also likely to block in vivo binding of LATS to the thyroid, and to reduce its rate of elimination from the circulating blood. The results are consistent with the assumption that the receptor structures and site of action of LATS and TSH in the thyroid are identical.

On the basis of these findings the possibility arises that high titres of antimicrosomal antibodies in the serum may interfere with the results of LATS bioassay in such patients. Moreover, it seems reasonable to assume that in Hashimoto's thyroiditis high levels of antimicrosomal antibodies reduce the TSH sensitivity of thyroid, leading to an enhanced secretion of TSH and promoting the development of hypothyroidism.
STIMULATING EFFECT OF DIBUTYRYL CYCLIC ADENOSINE 3′, 5′ MONOPHOSPHATE ON PROTEIN SYNTHESIS IN A THYROIDAL CELL-FREE SYSTEM AT LOW POTASSIUM AND SODIUM CONCENTRATIONS
Authors: Wägar Gustav
Published: December 2008

The aim of the present study was to investigate the effect of dibutyryl cyclic adenosine 3′, 5′ monophosphate (db-cAMP) on the L-14C-leucine incorporation into TCA-precipitable protein in a thyroidal microsomal cell-free system at low cation concentrations. The basic incubation system contained the following cation concentrations: 18 mm K+, 2.5 mm Na+ and 6 mm Mg2+.

Db-cAMP caused a linear stimulation of leucine incorporation in concentrations from 0.5 to 2.5 mm. When the K+ concentration was increased from 18 to 72 mm the stimulating effect of 2.5 mm db-cAMP decreased from 48 to 6 % while the basic incorporation level increased simultaneously. An increase in Na+ from 2.5 to 42.5 mm caused a similar incorporation curve. The optimal concentration of Mg2+ was 6 mm at which concentration the enhancement of leucine incorporation by db-cAMP was most pronounced. Low Ca2+ concentrations did not affect the db-cAMP response. At concentrations over 1 mm, Ca2+ inhibited the protein synthesis without lowering the relative stimulation caused by db-cAMP.
THE INFLUENCE OF CORTISOL ON 2-DEOXYGLUCOSE PENETRATION AND PHOSPHORYLATION BY THE MOUSE EAR STRIP PREPARATION
Authors: Ariyoshi Yutaka , Plager John , Matsui Nobuo
Published: December 2008

The influence of cortisol on 2-deoxyglucose (2-DG) penetration and phosphorylation was studied using the mouse ear strip preparation. The inhibitory effect of cortisol on 2-DG metabolism was first detectable only after a 1 h pre-incubation with cortisol. Cortisol inhibition of 2-DG phosphorylation became evident within 5 min after the addition of 2-G to the incubation medium, a significant inhibition of 2-DG penetration being induced 2 h later. This latter observation is interpreted as reflecting that small differences in intracellular 2-DG between the control and the experimental flasks would be masked by the variation within larger extracellular 2-DG pools during the early time periods. In longer incubation the rate of 2-DG phosphorylation slowed or stopped after 5 h of incubation and hence the increase of intracellular 2-DG accumulation had to be considered. At later time periods, cortisol inhibition of 2-DG penetration became clearly evident. The data are considered to be most consistent with a cortisol effect resulting in a decreased penetration of this sugar through the cell membrane.
BLOCKADE OF THE SURGE OF PROLACTIN AT PRO-OESTRUS BY ADMINISTRATION OF ANTI-OESTROGENIC SUBSTANCE, MER-25
Authors: Yokoyama Akira , Tomogane Hiroshi , Ôta Katuaki
Published: December 2008

A non-steroidal oestrogen antagonist, MER-25, was administered to cycling rats for elucidating the role of oestrogen in the surge of prolactin observed on the afternoon of pro-oestrus (POe).

In animals injected with 20 mg of MER-25 intramuscularly on the afternoon (16.30 h) of the first day of dioestrus (D-1), the surge of prolactin was blocked while the level of prolactin on the afternoon of POe of these animals was significantly higher than that of the corresponding controls injected with oil. Ovulation was also blocked in these animals treated with the drug on the afternoon of D-l. On the other hand, treatment on the morning (10.30 h) of the 2nd day of dioestrus failed to prevent not only the surge of prolactin but also ovulation.

These observations provide strong evidence for the view that oestrogen is responsible for the surge of prolactin on the afternoon of POe, and that the surge is accompanied by that of LH.
BIOTRANSFORMATION OF PREGNENOLONE AND PROGESTERONE BY RABBIT OVARIAN FOLLICLES AND CORPORA LUTEA
Authors: YoungLai Edward V.
Published: December 2008

Rabbit ovarian follicles obtained prior to and after mating and corpora lutea (24 h and 48 h post-coitus) were incubated with radioactive pregnenolone and progesterone to determine whether these substrates could serve as precursors of androgens and oestrogens. Incubations were carried out for 3 h in Hanks balanced salt solution: medium 199: normal rabbit serum: 55:30:15. Granulosa cells and corpora lutea converted pregnenolone to progesterone but no labelled oestrogens could be detected. Trace amounts of androgens were synthesized by the granulosa cells. Whole sliced follicles and theca formed progesterone from pregnenolone and androgens from both substrates. Oestradiol-17β was only synthesized by the whole sliced follicles and in one experiment by theca cells. Mating caused an increase in the 3β-hydroxysteroid dehydrogenase for pregnenolone and formation of testosterone but no oestrogens by the theca cells. These results indicate that both theca interna and granulosa cells are needed for oestrogen biosynthesis by rabbit follicles.
BIOLOGICAL ACTIVITY OF SYNTHETIC HUMAN CORTICOTROPHIN WITH REVISED AMINO ACID SEQUENCE
Authors: Schenkel-Hulliger Lotte , Maier René , Barthe Pierre L. , Desaulles Pierre A. , Jarret Andrée , Riniker Bernhard , Rittel Werner , Sieber Peter
Published: December 2008

The corticotrophic, melanotrophic and lipolytic activity of synthetic human corticotrophin of revised structure has been evaluated and compared with that of synthetic porcine ACTH (uncorrected structure). The amino acid sequence of the two peptides differs at 3 sites in the 25 to 31 region. The two peptides exihibit identical biological activities in in vitro and in vivo test systems in the rat.
IMMUNOREACTIVE GROWTH HORMONE IN PLASMA AND URINE IN JUVENILE DIABETICS BEFORE AND DURING INITIAL INSULIN TREATMENT
Authors: Hanssen Kristian F.
Published: December 2008

Twenty newly diagnosed, but as yet untreated patients of both sexes with classical juvenile diabetes were investigated by determining the mean plasma immunoreactive growth hormone (IRHGH) and urinary IRHGH for a 24 hour period before and during initial insulin treatment.

The plasma IRHGH was significantly higher (0.05 > P > 0.01) before than during initial insulin treatment.

During initial insulin treatment, the mean plasma IRHGH was significantly higher (0.01 > P > 0.001) than in a control group.

The urinary IRHGH was significantly higher (0.01 > P > 0.001) before than during insulin treatment.

The increased urinary IRHGH observed before insulin treatment is thought to be partly due to a defective renal tubular reabsorption of growth hormone.

No significant correlation was found between the mean blood sugar and plasma or urinary IRHGH either before or during insulin treatment.
INSULIN RESPONSE TO GLUCOSE INFUSION DURING PREGNANCY. A PROSPECTIVE STUDY OF HIGH AND LOW INSULIN RESPONDERS WITH NORMAL CARBOHYDRATE TOLERANCE
Authors: Edström Karin , Cerasi Erol , Luft Rolf
Published: December 2008

A decreased insulin response to glucose administration has been suggested to be a prerequisite for the development of diabetes mellitus. Factors that increase the demand for insulin in the organism may precipitate diabetes in subjects with a low insulin response to a glucose infusion test (GIT). Since it is well-known that pregnancy is a diabetogenic factor, its effect on the carbohydrate metabolism of subjects with a low insulin response was studied.

During pregnancy, the insulin response of the low responders was enhanced as in the controls, but at all stages the insulin response was significantly less than in the controls. None of the subjects developed glucose intolerance during pregnancy. The fasting blood glucose and plasma insulin levels and the k-value in intravenous glucose tolerance tests (IVGTT) were modified according to similar patterns in both groups. The sensitivity to endogenous insulin was significantly greater in the low insulin responders but was reduced to a greater extent than in the controls towards the end of pregnancy.

In four of the 11 low insulin responders the initial insulin response to glucose in the last trimester was lower than in mid-pregnancy. This occurred only in one out of 14 high insulin responders.

It is suggested that gestational diabetes occurs in those low insulin responders who demonstrate either a dramatic decrease in insulin sensitivity, or limitations in the enhancement of insulin release, or, more likely both conditions.
CORTISOL BINDING CAPACITY IN PLASMA DURING ANAESTHESIA AND SURGERY
Authors: Kehlet Henrik , Binder Christian , Engbæk Christen
Published: December 2008

The transcortin binding capacity and cortisol binding to albumin were determined before and after induction of anaesthesia and also post-operatively in 14 normal subjects undergoing major surgery. Plasma non-protein-bound (free) cortisol and total cortisol in the plasma were measured by an ultrafiltration technique and a competetive protein-binding technique, respectively.

The results showed that the anaesthetics caused a decreased (0.05 < P < 0.1) binding of cortisol to albumin, while the transcortin binding capacity was unchanged. Post-operatively the mean transcortin binding capacity decreased from 24.6 to 20.4 μg cortisol per 100 ml (P < 0.01) and the cortisol binding to albumin returned to pre-anaesthetic values. These findings could not be related to changes in the concentration of albumin, α2-protein and total protein in plasma.
HYPERRESPONSIVENESS TO LYSINE-VASOPRESSIN IN CUSHING'S DISEASE
Authors: Coslovsky Rafael , Wajchenberg Bernardo Léo , Nogueira Otilia
Published: December 2008

The lysine-8-vasopressin (LVP)-test was performed in 11 normal subjects, with pituitary-dependent Cushing's disease and in 3 cases of Cushing's syndrome due to an adrenocortical carcinoma. The plasma 17-hydroxycorticosteroids response to LVP in Cushing's disease was compared with the response of the normal controls. It is concluded that patients with pituitary-dependent Cushing's syndrome are hyper-responsive to LVP. The possible mechanisms of this hyper-responsiveness are discussed: release of ACTH from the pituitary and/or an increased release of cortisol from the hyperplastic adrenals may occur. As expected, patients with Cushing's syndrome due to an adrenocortical carcinoma did not respond to LVP.

It is suggested that the LVP-test can be used for the diagnosis of Cushing's syndrome and for the differential diagnosis between Cushing's disease and Cushing's syndrome due to an adrenocortical carcinoma, although it is recognized that in some cases this test will not be adequate.
CONJUGATION OF 16-EPIOESTRIOL BY PREGNANT WOMEN
Authors: la Torre B. de , Wiqvist N. , Diczfalusy E.
Published: December 2008

[4-14C,16α-3H]16-Epioestriol (1,3,5(10)-oestratriene-3,16β,17β-triol) has been synthesized and tracer amounts were administered to two women in the form of an intravenous infusion two days prior to the interruption of gestation. Various conjugated forms of 16-epioestriol were isolated and identified by their conversion into the completely methylated derivatives, subsequent hydrolysis and crystallization to constant isotopic ratio. The quantitatively most important conjugate was the 16-glucosiduronate, followed by the 3,16-diglucosiduronate and the 3-sulphate,16-glucosiduronate. No 3-glucosiduronate or 3-sulphate was isolated. There was a changing pattern of conjugation with time: during the first six hours of urine collection the 16-glucosiduronate was predominant, whereas during the subsequent six hours the 3,16-glucosiduronate was the quantitatively most important conjugate.

Part of the administered 16-epioestriol was recovered from each urine specimen in the form of oestriol.
AN IMPROVED TECHNIQUE FOR MEASURING SOMATOMEDIN ACTIVITY IN VITRO
Authors: Van den Brande J. L. , Caju M. V. L. Du
Published: December 2008

A method for measuring somatomedin activity in vitro is described. Porcine costal cartilage fragments are prepared and incubated using a special dissection and incubation apparatus. The schedule consists of a 24 h pre-incubation, 46 h of incubation with the test substance and 3 h of post-incubation in a medium containing both 35S-Na2SO4 and 3H-thymidine. The average index of precision is 0.15 for 35S-uptake and 0.19 for 3H-thymidine. Although the assay is less sensitive than the hypophysectomized rat assay, it yields a considerable increase in precision, it is far less laborious to perform and is not so expensive.
A COMPARATIVE STUDY OF DEHYDROEPIANDROSTERONE AND DEHYDROEPIANDROSTERONE SULPHATE DYNAMICS BY THE "URINARY" AND "BLOOD APPROACH" UNDER PHYSIOLOGICAL CONDITIONS
Authors: Fehér T. , Halmy L.
Published: December 2008

The dynamic parameters of dehydroepiandrosterone and dehydroepiandrosterone sulphate metabolism have been determined following a single injection of [4-14C] dehydroepiandrosterone and [7α-3H] dehydroepiandrosterone sulphate into normal female subjects. The urinary secretion and production rates, the ϱDDS and ϱDSD conversion factors, the metabolic clearance rates, blood production rates and distribution volumes were calculated. Although the comparison between urinary and blood parameters of steroid dynamics suggested certain limitations of the methods used, they were found suitable for gaining information on dehydroepiandrosterone and dehydroepiandrosterone sulphate metabolism. A poor extra-adrenal conversion of dehydroepiandrosterone to the sulphate, small dehydroepiandrosterone sulphate and large dehydroepiandrosterone distribution volumes or clearance patterns, and a possible correlation between the blood parameters of dehydroepiandrosterone sulphate and anthropomorphology of normal female subjects were found.
ACCENTUATION BY ANGIOTENSIN II OF THE ANTIDIURETIC AND DIPSOGENIC RESPONSES TO INTRACAROTID INFUSIONS OF NaCl AND FRUCTOSE
Authors: Olsson Kerstin , Kolmodin Rigmor
Published: December 2008

Infusions of angiotensin II (angiotensin) into the lateral cerebral ventricle of hydrated goats were made alone, or in combination with intracarotid infusions of hypertonic NaCl. The dose of angiotensin used (0.3 ng/kg min) had negligible antidiuretic, and no dipsogenic effect of its own. However, it markedly potentiated the antidiuretic hormone (ADH) releasing effect of intracarotid infusions of hypertonic NaCl, and made these infusions become dipsogenic.

When angiotensin was infused together with hypertonic NaCl into the carotid artery, a 15 times higher dose had to be administered to obtain a comparable degree of potentiation. The results confirm that Na+ and angiotensin interact in the central control of water balance and support the view that receptors sensitive to changes in the Na+ concentration of the cerebrospinal fluid play a role in this control.

When infused into the carotid artery together with hypertonic fructose, angiotensin also enhanced the ADH-releasing effect of the fructose infusions. If this reflects a central sodium-angiotensin interaction, it would indicate that the intracarotid infusion of hypertonic fructose affects the formation of cerebrospinal fluid in such a manner as to cause a rise in its Na+ concentration.
IN VITRO METABOLISM OF STEROID HORMONES BY CHICKEN BRAIN
Authors: Nakamura Takao , Tanabe Yuichi
Published: December 2008

The brains of 14-month-old White Leghorn cocks were homogenized, fractionated by differential centrifugation, and used as enzymatic materials. When [4-14C]pregnenolone was incubated with the brain homogenate, the substrate was recovered without conversion. After incubation of [4-14C] progesterone with the brain homogenate, it was converted to 5α-pregnanedione and 3α-hydroxy-5α-pregnan-20-one. When [4-14C]17α-hydroxyprogesterone was incubated with the brain homogenate, it was metabolized to androstenedione, 3α, 17α-dihydroxy-5α-pregnan-20-one and 17α,20α-dihydroxy-4-pregnen-3-one. [4-14C] Androstenedione was metabolized to 5α-androstanedione, testosterone, androsterone, epiandrosterone and 5α-androstanediol; and [4-14C]testosterone was metabolized to androstenedione, 5β-dihydrotestosterone and 5β-androstanediol in the chicken brain. The enzymatic pattern in the brain of cocks was characterized by high activities of the 17β-hydroxysteroid dehydrogenase. Δ4-5β- and Δ5-5β-hydrogenase which acted on both C19- and C21-steroids, but was lacking in Δ5-3β-hydroxysteroid dehydrogenase associated with the Δ5a-Δ4isomerase, and 17α-hydroxylase.
LH-RH TEST IN 100 PATIENTS WITH OVARIAN INSUFFICIENCY
Authors: Czygan P.-J. , Breckwoldt M. , Lehmann F. , Langefeld R. , Bettendorf G.
Published: December 2008

The effect of synthetic LH-RH was studied in 100 patients with various types of ovarian insufficiency by following up the FSH- and LH-levels in plasma. LH-RH was administered in doses of 12.5, 25 and 100 μg as a rapid intravenous injection. The patients were classified according to the endocrine state of the pituitary as evidenced by the urinary gonadotrophin levels. A clear correlation between the functional state of the pituitary and its responsiveness to exogenous LH-RH was demonstrated. Most of the patients with undetectable low urinary gonadotrophin levels failed to respond. The majority of patients with gonadotrophin excretion in the normal range and those with elevated levels reacted with a dose dependent increase in circulating LH. The amount of liberated FSH however was related to the injected dose only in patients with high gonadotrophic excretion.

The present study indicates that synthetic LH-RH provides a useful tool in the evaluation of the pitutiary function particularly in patients with low and with undetectable gonadotrophin excretion. The data presented in this paper also demonstrate that the functional state of the pituitary is clearly reflected by the urinary gonadotrophin levels.
THE DEVELOPMENT OF AN IN VITRO SYSTEM FOR ESTIMATING OXYTOCINASE IN THE RABBIT HYPOTHALAMUS AND THE EFFECTS OF SOME PROTEIN SYNTHESIS INHIBITORS AND OESTRADIOL-17β ON ENZYME ACTIVITY
Authors: Frith Dona A. , Hooper K. C.
Published: December 2008

An in vitro system for investigating the effects of steroid hormones and protein synthesis inhibitors on hypothalamic peptidases inactivating oxytocin has been developed.

In the presence of oestradiol-17β enzyme activity was increased in the in vitro system whilst this increase was blocked completely by cycloheximide and partially blocked by actinomycin-D. It is apparent therefore that oestradiol-17β acts directly on the hypothalamus stimulating oxytocinase activity.
RAPID ESTIMATION OF HUMAN CHORIONIC SOMATOMAMMOTROPHIN (HCS) BY HAEMAGGLUTINATION INHIBITION AND COMPARISON OF RESULTS WITH RADIOIMMUNOASSAY
Authors: Spona J. , Töpert M.
Published: December 2008

A method of haemagglutination inhibition assay of HCS was developed utilizing formaldehyde and glutaraldehyde to conjugate the hormone to sheep red blood cells. This technique is sufficiently sensitive (8.7 ng/ml) so that assay of HCS from early pregnancy serum (17 weeks of gestation) can be performed directly after 1:50 dilution. Results can be obtained within 3 h. HCS sensitized red blood cells were shown to be stable for several months.

HCS levels of 20 normal pregnancies were estimated throughout gestation. Forty-two sera from pregnant subjects were assayed by this technique and radioimmunoassay (RIA). The values obtained by the 2 methods had excellent correlation (r = 0.95). Reproducibility of the present method was ± 15 %. Data of HCS serum levels obtained by the present technique and by RIA in high-risk pregnancies are compared and the conclusion is reached that any of these techniques can be used for the successful clinical assay of HCS.
THE TRANSPLACENTAL PASSAGE OF THYROXINE AND FOETAL THYROID FUNCTION IN THE RAT
Authors: Gray Barry , Galton Valerie Anne
Published: December 2008

A study has been made of the transplacental passage of thyroxine (T4) in rats when the hormone is present in physiological concentrations, and of the activity of the foetal thyroid gland in the perinatal period. Several aspects of foetal thyroid function were assessed in intact and thyroid-ectomized (TX) pregnant rats maintained with graded doses of T4. A daily dose of 2 μg T4/100 g body weight yielded near normal maternal and foetal serum PBI levels; with a dose of 1 μg the values were slightly low. Both these doses resulted in a decrease in the total and T4 iodine content of the foetal thyroid; an even greater decrease occurred in rats maintained with 5 μg/100 g body weight/day. The rate of uptake of iodine by the foetal gland was significantly depressed by the 2 but not the 1 μg dose. Serum PBI levels in the foetus were related directly to the dose of T4 and inversely with the degree of depression of the thyroid gland. Both maternal and foetal serum PBI levels in the unsupplemented TX rats were at least 60 % of normal and there was evidence of increased secretion of T4 by the foetal thyroid. The data indicate that the placenta is readily permeable to T4 when the hormone is present in maternal serum in doses that are close to physiological. However it was not possible to estimate the extent of the placental transfer of endogenous hormone. Significant foetal thyroid function was evident near term. It is suggested that both the foetal and maternal thyroids contribute to the maintenance of serum T4 levels in the foetus.
INSULIN EFFECTS ON CALCIUM, MAGNESIUM AND PHOSPHATE METABOLISM IN RATS
Authors: Mellerup Erling T.
Published: December 2008

Serum calcium as well as serum magnesium increased after insulin administration to rats. The increase in serum calcuim was followed by a decrease, which did not occur in thyroid-parathyroidectomized animals. The increase in both serum calcium and magnesium may be secondary to a diminished uptake of calcium and magnesium into bone. On the other hand this may be secondary to a decreased uptake of phosphate into bone. The decreased uptake of phosphate into bone may be secondary to the decrease in serum phosphate, which is a well-known phenomenon after insulin administration.

In addition to all these indirect effects, insulin directly increased the uptake of magnesium into muscle and probably also the liver, thus counteracting the increase in serum magnesium.
INCREASED STEROID METABOLIC CLEARANCE RATE IN ANEPHRIC PATIENTS
Authors: Corvol P. , Bertagna X. , Bedrossian J.
Published: December 2008

The control of plasma aldosterone level depends on the secretion rate and on the metabolic clearance rate (MCR) of the hormone. The rate of aldosterone metabolism was measured in 6 anephric patients in comparison with normal volunteers. Unexpected high aldosterone MCR's were found in the anephric patients: 2700 ± 265 1/24 h (M ± sem), as compared to the normals (1600 ± 57). Passive 45° tilting did not significantly change aldosterone MCR's in both the normal and anephric patients. This increase in aldosterone MCR might be explained by a high hepatic plasma flow due to a high cardiac output. The haemodynamic condition of these patients could also explain the high testosterone MCR found in 3 male anephric patients, although testosterone-oestradiol binding globulin was in the high normal male range.
URINARY FOLLICLE STIMULATING HORMONE CHORIONIC GONADOTROPHIN AND OESTROGENS DURING HUMAN PREGNANCY
Authors: Watanabe Noboru , Seki Mitsunori , Seki Katsuyoshi , Yoshihara Terufumi
Published: December 2008

Concentrations of follicle stimulating hormone (FSH) and human chorionic gonadotrophin (HCG) were measured in randomly voided urine of 50 women during pregnancy by double antibody radioimmunoassay. Daily 24 h urine specimens were also collected once a week from 4 pregnant women from the early period of pregnancy up to delivery. In the 4 women, pregnancy was induced by the treatment with ovulatory agents. Urinary total oestrogens excretion as well as the FSH and HCG excretions were determined in the 24 h specimens. In the randomly voided urine, the concentration of FSH showed a tendency to increase progressively until term. The concentration of HCG was highest at weeks 9–12. Similar patterns of both the urinary FSH and HCG excretions were found in the serially collected 24 h specimens. However, continuous fluctuation in the FSH excretion was observed in two of the four cases followed throughout pregnancy. The urinary excretions of total oestrogens in 24 h specimens showed a relatively steady rise from week 16 and reached a peak before the onset of delivery. The excretion of total oestrogens as well as HCG showed a rapid fall after delivery.
STIMULATION BY STEROIDS AND AGE-DEPENDENT CHANGES OF L-CYSTINE ARYLAMIDASE ACTIVITY IN THE HYPOTHALAMUS OF THE RAT
Authors: Kuhl Herbert , Rosniatowski Christian , Bickel Martin , Taubert Hans-Dieter
Published: December 2008

L-cystine arylamidase activity was found to be high in hypothalamic homogenates from 10 day old rats, and then to decrease significantly until sexual maturity was reached (P < 0.01). This enzyme activity could be stimulated by treating 10 to 35 day old male rats with 100 μg of testosterone. Contrary to this, L-cystine arylamidase activity could not be stimulated in female animals by the injection of 7 μg of ethinyl-oestradiol before Day 45 of life. These data are interpreted as meaning that the L-cystine arylamidase activity plays a rôle in the processes regulating sexual maturation.
THE EFFECT OF THYROTROPHIN RELEASING HORMONE ON THE RELEASE OF THYROTROPHIN AND OTHER PITUITARY HORMONES IN MAN UNDER BASAL CONDITIONS AND FOLLOWING ADRENERGIC BLOCKING AGENTS
Authors: Nilsson K. O. , Thorell J. I. , Hökfelt B.
Published: December 2008

Studies were performed in nine healthy male volunteers to evaluate the effect of the iv injection of 200 μg of thyrotrophin releasing hormone (TRH) on the blood concentrations of various anterior pituitary hormones, thyroxine and cortisol before and following treatment with propranolol and phentolamine, respectively. The influence on the free thyroxine index was also studied.

In all subjects TRH was followed by an increase in plasma thyrotrophin (TSH) with a maximum 20–30 minutes after the injection. The increase in TSH was significantly less after treatment with phentolamine as compared to no treatment (P<0.05; paired t-test) and propranolol (P<0.02), respectively. Thus, our studies could indicate that adrenergic receptors are of importance for the TRH induced release of TSH.

The plasma concentration of thyroxine and the free thyroxine index both increased significantly after TRH under all conditions studied.

TRH induced no changes in the plasma levels of growth hormone, follicle stimulating hormone, luteinizing hormone and serum cortisol, indicating that TRH has a rather specific effect on the production of TSH. This specificity is not altered by either alpha- or beta-blocking agents.
ADRENAL CONTRIBUTION TO PLASMA OESTROGENS IN ADRENAL DISORDERS
Authors: Yuen Basil Ho , Kelch Robert P. , Jaffe Robert B.
Published: December 2008

The concentrations of oestrone (Oe1) and oestradiol (Oe2) in adrenal venous and peripheral plasma (inferior vena cava, aorta and/or antecubital vein) were measured by radioimmunoassay in 8 patients in whom an adrenal disorder was suspected (group A) and 5 patients in whom an adrenal disorder was proven (group B). In group A, 6 patients had higher Oe1 concentrations in adrenal than in peripheral plasma, while 5 patients had higher Oe2 concentrations in adrenal venous plasma. In group B, in 3 of 4 patients with primary aldosteronism secondary to an adrenocortical adenoma, both Oe1 and Oe2 concentrations in the adrenal venous plasma from the side of the adenoma were greater than in peripheral plasma. A patient with Cushing's disease showed a similar gradient for Oe1 but not Oe2.

The results are consistent with the following conclusions: 1) Both Oe1 and Oe2 are secreted from the adrenal in neoplastic and non-neoplastic disorders in detectable but small amounts. 2) Estimates of maximal adrenal secretion rates in 3 male patients indicate that the adrenal contribution was less than 4 % (Oe1) and less than 2 % (Oe2), of reported blood production rates of oestrogens in normal men.
THE IN VITRO EFFECT OF PROGESTERONE AND OESTROGENS ON THE SPONTANEOUS AND OXYTOCIN-INDUCED ACTIVITY OF THE HUMAN MYOMETRIUM
Authors: Barnafi L. , Larraguibel R.
Published: December 2008

The in vitro effect of progesterone and oestrogens on the spontaneous and oxytocin-induced activity of the pregnant and non-pregnant human myometrium was studied.

Oestrogens as well as progesterone blocked the spontaneous and oxytocininduced contractions 10–20 min after the steroids were added to the bath. The inhibitory effect was dose-dependent and reversible. Oestradiol-17β and diethylstilboestrol were approximately 10 times more active than progesterone.

The possible mechanism of action of oestrogens and progesterone are discussed.
THE INFLUENCE OF ETHANOL ON THE CONVERSION OF PREGNENOLONE TO PROGESTERONE BY HUMAN PLACENTAL MICROSOMES
Authors: Lübbert H. , Pollow K. , Wagner R. , Hammerstein J.
Published: December 2008

The effects of ethanol on kinetic parameters of placental Δ5-3β-hydroxysteroid dehydrogenase were studied. In the presence of high pregnenolone concentrations (50 μm, [S] > Km) the microsomal enzyme preparation exhibited an almost linear increase in activity as the ethanol concentration in the medium was raised from 2.5 to 15 % (v/v). At lower substrate concentrations ([S] << Km) ethanol caused inhibition. Other effects of ethanol were: linearity of product formation with time was prolonged; the maximal velocity was markedly increased; the Km for pregnenolone slightly decreased with increasing ethanol concentrations (2.5 to 10 %, v/v) whereas the Km for NAD remained the same. The pH and temperature optima of the reaction were unaffected by ethanol. Other organic solvents caused similar effects.
PITUITARY-GONADAL INTERRELATIONSHIPS IN PUBERTAL FEMALE SUBJECTS
Authors: Adamopoulos D. A. , Loraine J. A. , Lunn S. F. , Mackay M. A. , Forfar J. O.
Published: December 2008

Hormone assays in urine were conducted serially in four girls for 28 to 78 days each year for a period of four or five years. Assays of the three classical oestrogens and pregnanediol were made throughout this time; total gonadotrophins were estimated during the first two years and FSH and/or LH in subsequent years. Oestrogen output rose gradually throughout, evidence of variation in hormonal activity being noted from the second year onwards. In two of the girls who menstruated in the fourth year, the pattern of oestrogen excretion was similar to that of adult women during reproductive life. Pregnanediol output was generally low, tended to rise with increasing age, and from the second year onwards levels fluctuated. Ovulation, as judged by pregnanediol assays, occurred in two out of the nine cycles studied. Total gonadotrophic activity was low in the first year and rose in the second. In the third year FSH output was at the lower end of the range of values occurring in young normally menstruating women and was within this range during the fifth year. LH activity was low when first estimated, rose slightly in the fourth year, and showed a typical adult pattern, including a midcycle peak, in the fifth. The investigation demonstrated a progressive rise in steroid and gonadotrophin output in pubertal female subjects as they increased in stature, developed secondary sex characteristics and approached the menarche; the increase was associated with marked fluctuations in hormonal activity well in advance of the first menstrual bleeding. The physiological significance of these bleedings is discussed, and it is emphasised that the study as a whole provides a useful framework for the investigation of pathological conditions occurring at or about the time of puberty.
EFFECT OF IODIDE AND THYROTROPHIN ON IN VITRO 14C-AMINO ACID INCORPORATION INTO RAT THYROID PROTEINS
Authors: Valenta Lubomir J.
Published: December 2008

Thyroid lobes from rats on normal (NID) or low iodine (LID) intake were incubated for 4 hours in vitro in the presence of 14C-amino acids. The 14C-amino acid incorporation into thyroid protein was significantly higher in thyroids from LID than from NID fed rats, 7.82 ± 1.01 % (mean ± sd) of total radioactivity of the incubation mixture per 100 mg tissue compared to 3.74 ± 0.60 % respectively. Thyrotrophin (TSH) in vitro did not influence the 14C-amino acid incorporation. Iodide in concentration 10−7 m and higher decreased 14C-radioactivity incorporation into protein by 19.40 ± 3.06 and 26.59 ± 4.06 % of the control value for NID and LID rats respectively. This effect of iodide did not depend on iodine organification and was not influenced by the changes of free amino acids pool. There were no significant differences in the relative concentration of 14C-labelled thyroglobulin and total 14C-thyroid protein. Differential fragility demonstrable by unfolding or dissociation was observed between different classes of thyroglobulin. The fragility was increasing from the old non-labelled molecules to newly iodinated and newly synthesized ones. It is concluded that iodide has a direct intrathyroidal blocking effect on thyroid protein synthesis which may contribute to its antigoitrogenic action. The lack of in vitro stimulation of protein synthesis by TSH remains unexplained.
THE EFFECTS OF CALCITONIN ON THE METABOLIC DISTURBANCES SURROUNDING WIDESPREAD BONY METASTASES
Authors: Parsons V. , Dalley V. , Brinkley D. , Davies C. , Vernon A.
Published: December 2008

Seven patients with widespread bony metastases, with and without hypercalcaemia were given porcine or salmon calcitonin in an attempt to reduce that rate of progression of their disease, possibly to reduce pain and to accelerate healing during the course of other endocrine therapy. The latter included the administration of phosphate, steroids, androgens or oestrogens and hypophysectomy. Calcitonin effects were seen to be enhanced by simultaneous administration of phosphate and possibly antagonised by oestrogens. The metabolic changes that did occur, suggested that the rate of healing of metastatic bone disease was increased and the mechanisms of these changes are discussed.
CALCIUM AND STIMULUS-SECRETION COUPLING IN THE NEUROHYPOPHYSIS
Authors: Russell J. T. , Thorn N. A.
Published: December 2008

Groups of 10 hemilobes of rat neurohypophyses were stimulated for 10 min in a medium containing 56 mm K+ or by application of a field current (20 Hz, 2 msec, 40 mA). Both stimulations resulted in a 5 to 8 fold increase in the release of vasopressin which was inhibited (in a dose-related manner) by addition to the medium of various blockers of calcium transport: LaCl3 (4 × 10−4, 4 × 10−3 m/l), prenylamine (2 × 10−5, 1 × 10−4 m/l) and D600, a verapamil derivative (4 × 10−6, 1 × 10−5, 2 × 10−5 m/l). Increasing the Ca2+ concentration in the medium to 14 mm abolished the inhibitory effect of D600. D600 also inhibited vasopressin release caused by introducing Ca2+ into a Ca2+-free medium during continued electrical stimulation.

Efflux of 45Ca2+ from neural hemilobes labelled during incubation in a 56 mm K+ containing medium was markedly increased during stimulation with a 56 mm K+ medium or electrical current. Lanthanum (4 × 10−3 m/) and D600 (2 × 10−5 m) inhibited this increased efflux as well as hormone release.

When the hemilobes had been pre-labelled in a medium with 4.8 mm K+, stimulation during efflux, by 56 mm K+ or electrical current, caused hormone release comparable to that seen after labelling in 56 mm K+, but with neither type of stimulation was there any significant increase in 45Ca2+ efflux.

These findings would appear to be in agreement with a hypothesis that very small amounts of Ca2+ enter the endings of the neurosecretory neurons on stimulation (thereafter possibly releasing intracellular calcium) and that calcium entry is essential in inducing hormone release. The uptake of calcium over the neurosecretory nerve membrane apparently has several of the characteristics shown for calcium entry on stimulation of the squid axon.
EFFECT OF AMINOPHYLLINE ON GROWTH HORMONE SECRETION IN MAN
Authors: Peracchi M. , Cavagnini F. , Pontiroli A. E. , Raggi U. , Malinverni A. , Pinto M.
Published: December 2008

The effects of intravenously administered aminophylline on growth hormone (GH) secretion have been studied in sixteen normal subjects and four acromegalic patients.

Intravenous infusion of theophylline ethylenediamine 480 mg over a 30 min period did not alter the blood glucose and serum GH levels in six normal subjects but raised the plasma FFA by 88 %. By contrast, in four acromegalic patients theophylline administration resulted in a fall of the serum GH levels by 17.6–51.7 %, mean 36.5%. In ten normal subjects the infusion of the drug clearly blunted the GH response to insulin hypoglycaemia without modifying the decrease in blood glucose and plasma FFA induced by insulin: mean peak GH values decreased from 32.7 ± 3.39 to 21.4 ± 4.10 ng/ml (P < 0.025).

These data seem to indicate that theophylline has an overall inhibiting effect on the hypothalamic-hypophyseal axis for GH secretion.