bluuebunny/crossref_metadata_2025_split huggingface dataset:
EFFECT OF METHYLERGOBASINE MALEATE ON SERUM GONADOTROPHIN AND PROLACTIN IN HUMANS
Authors: Perez-Lopez F. R. , Delvoye P. , Denayer P. , L'Hermite M. , Roncero M. C. , Robyn C. 
Published: December 2008

ABSTRACT
Intramuscular injection of 0.2 mg methylergobasine maleate3) (Methergin®, Sandoz) in women on day 3 post-partum, in regularly menstruating women and in adult men, is followed within 30 to 75 min by a 50 % decrease in serum prolactin concentration: the levels remain low until 180 min and increase between 180 and 240 min. The amplitude of the decrease is the same when prolactin is measured in terms of the same serum prolactin standard by a homologous ovine assay and by a homologous human assay. However, in the case of regularly menstruating women and of men serum prolactin concentration is some three times higher when estimated by the ovine assay than when estimated by the human assay. This difference between assay results obtained by the two radioimmunoassay methods could be due to heterogeneity of serum prolactin. However, non-specific effects of serum are not excluded. In regularly menstruating women and in men, intramuscular injection of 0.2 mg methylergobasine maleate is followed within 45 to 75 min by a 50% decrease in immunoreactive serum LH concentration without concomtant change in immunoreactive FSH. The depression of LH secretion lasts for 1 to 2 h. The circulating levels of HCG in post-partum women are not modified after intramuscular injection of Methergin. In humans as in animals and in in vitro studies, inhibition of prolactin and LH release induced by ergot drugs are likely due to both an indirect effect via the hypothalamus and to a direct effect on the pituitary cells.
Finally, these data suggest that, because of its interference with prolactin secretion, intensive treatment with ergot drugs during the post-partum period may impair lactation.
PLASMA PROLACTIN LEVELS AFTER TRH AND CHLORPROMAZINE IN NORMAL SUBJECTS AND PATIENTS WITH IMPAIRED PITUITARY FUNCTION
Authors: Schwinn G. , von zur Mühlen A. , Köbberling J. , Halves E. , Wenzel K. W. , Meinhold H. 
Published: December 2008

ABSTRACT
Basal plasma prolactin levels and values after stimulation with TRH and chlorpromazine respectively were measured. TRH tests were performed in 50 healthy subjects (25 women and 25 men). The basal prolactin levels and the maximum increment were found to be as follows in women 22.02 ng/ml ± 5.02 sem and 100.0 ng/ml ± 11.3 sem respectively, in men 16.62 ng/ml ± 2.46 sem and 45.26 ng/ml ± 5.70 sem respectively. The maximum prolactin increase after chlorpromazine in 6 men amounted to 64.77 ng/ml ± 8.28 sem respectively and in 12 women, 6 of them taking hormonal contraceptives, 81.0 ng/ml ± 16.53 sem. There was no significant difference between the 2 groups of women.
The behaviour of plasma prolactin under stimulation in patients with impaired pituitary function was compared with the other trophic pituitary functions before therapy, in 7 patients before and after hypophysectomy and 15 patients only after therapy. In addition 6 patients with tumours adjacent to the pituitary and 3 women with Sheehan's syndrome were investigated. Plasma prolactin before and after stimulation was not pathologically changed in all cases. After surgery the prolactin levels were also normal in many patients. In most of them slight or marked elevation of prolactin levels were found.
There was no good correlation between the trophic pituitary functions in most cases. It seems that prolactin measurement under stimulation conditions is the most sensitive indicator of a residual pituitary function.
AN IMPROVED TECHNIQUE FOR TRANSAURICULAR HYPOPHYSECTOMY AND AUTOTRANSPLANT OF ISOLATED PIECES OF PARS INTERMEDIA TISSUE IN THE EVACUATED PITUITARY CAPSULE OF THE RAT
Authors: Naik D. V. , Sheriff T. Abdul Qadir 
Published: December 2008

ABSTRACT
An improved technique for transauricular hypophysectomy in rats, weighing 120–300 g, is described. This method can be used for transplantation studies, which is demonstrated by transplanting pars intermedia tissue into the evacuated pituitary capsule. Our technique has been carried out, successfully, in various laboratories. The success, however, depends upon the skill and care of the investigator.
THE PHARMACOLOGY AND METABOLISM OF TESTOSTERONE UNDECANOATE (TU), A NEW ORALLY ACTIVE ANDROGEN
Authors: Coert A. , Geelen J. , de Visser J. , van der Vies J. 
Published: December 2008

ABSTRACT
Testosterone undecanoate (TU), either dissolved in arachis oil or as micro-crystal suspension, displays androgenic activity on oral administration to rats in the Hershberger test. The solution in arachis oil is more active than the crystal suspension. When [3H]TU is administered orally to rats, most of it is metabolized in the intestinal wall. The majority of the metabolites probably lose their undecanoate group and are absorbed via the portal vein. The non-metabolized [3H]TU and at least two metabolites are absorbed exclusively via the lymphatic system. One of these metabolites has been identified as 5α-dihydrotestosterone undecanoate (5α-DHTU). TU has no harmful effects on the liver of the rabbits on oral administration.
THE BINDING OF INSULIN AND SOMATOMEDIN A TO HUMAN PLACENTAL MEMBRANE
Authors: Takano K. , Hall K. , Fryklund L. , Holmgren A. , Sievertsson H. , Uthne K. 
Published: December 2008

ABSTRACT
A particulate membrane fraction from human placental membrane was shown to be rich in binding sites not only for insulin but also for somatomedin A. The binding of the 125I-labelled peptide was time and temperature dependent. Degrading activity present in the membrane fraction was negligible at +4°C. The Scatchard plot for insulin binding revealed two types of binding sites with an apparent high affinity constant of 3.8× 108 m−1 and with 5.4 × 10−9 moles of binding sites per mg of membrane protein. The Scatchard analysis of somatomedin A revealed two classes of binding sites with an apparent high affinity constant of 2.7 × 107 m−1 and with 1.9× 10−8 moles of binding sites per mg of membrane protein. In high concentrations insulin interfered with the specific binding sites for somatomedin A and vice versa. In comparison with insulin the somatomedin A preparation was one million times more potent in displacing labelled somatomedin A than in displacing labelled insulin from their respective binding sites.
A radioreceptor assay utilizing particulate placental membrane and labelled somatomedin A purified on the membrane enabled the determination of somatomedin in unextracted serum. The mean values of somatomedin A in sera from patients with pituitary dwarfism and acromegaly were 0.57 and 3.2 U/ml, respectively by radioreceptor assay and 0.41 and 1.61 U/ml, respectively by bioassay. Various causes of this discrepancy between the methods are discussed.
THE RATE OF TRIIODOTHYRONINE DISSOCIATION FROM BINDING SITES IN HUMAN PLASMA
Authors: Hillier A. P. 
Published: December 2008

ABSTRACT
A method is described for estimating the rate of triiodothyronine (T3) dissociation from binding sites in human plasma. At trace concentrations about 25 % of the hormone dissociates rapidly, the reaction being more than half complete within 1 second. The remaining 75 % dissociates exponentially with a t½ of 4.2 seconds at 37–38°C. When the plasma is loaded with thyroxine to displace the T3 from thyroxine-binding globulin, the slow exponential reaction is lost and all of the hormone dissociates rapidly. These results indicate that the free and bound T3 in plasma are in a state of rapid exchange.
RADIOIMMUNOASSAYS OF 3,5,3′-TRIIODO-L-THYRONINE WITH AND WITHOUT A PRIOR EXTRACTION STEP
Authors: Burger A. , Sakoloff C. , Staeheli V. , Vallotton M. B. , Ingbar S. H. 
Published: December 2008

ABSTRACT
Two radioimmunoassays for triiodothyronine (T3) are described, one of which includes an extraction step, while the other does not. To raise antibodies, two carrier proteins and different coupling agents were used, namely haemocyanin and diazotized benzidine or human serum albumin and carbodiimide. In the case of T3 coupled to haemocyanin by diazotized benzidine, evidence of covalent binding of the hapten to the protein was obtained. In the case of T3 coupled to human serum albumin, little evidence of covalent linkage was available. Nevertheless immunization was successful in both cases.
The radioimmunoassay in unextracted serum was highly reproducible and precise (intra-assay variability 5.2% inter-assay variability 8.1%). Normal values were determined which clearly indicate a fall in the serum T3 concentration with increasing age. In men the fall occurs in the fifth decade. In women the T3 starts to fall only after 70 years of age. In 31 cases of hyperthyroidism the serum T3 concentration ranged from 2.26 to 10.4 ng T3/ml. In 10 cases of hypothyroidism the values ranged from 0 to 0.8 ng T3/ml.
The radioimmunoassay using an extraction procedure was less extensively used since it was found to be less reproducible (intra-assay variability 7.5%, inter-assay 12.25%). The normal values were determined with a mixed population aged 20–50. The mean ± 2 sd was 0.9 ± 0.36 ng T3/ml (n=52). In 17 cases of hypothyroidism the values ranged from 0 to 0.6 ng T3/ml and in 22 cases of hyperthyroidism from 2 to 14.4 ng T3/ml.
DIURNAL VARIATIONS OF PLASMA ALDOSTERONE IN SUPINE MAN: RELATIONSHIP TO PLASMA RENIN ACTIVITY AND PLASMA CORTISOL
Authors: Armbruster Helmut , Vetter Wilhelm , Beckerhoff Rainer , Nussberger Jürg , Vetter Hans , Siegenthaler Walter 
Published: December 2008

ABSTRACT
In order to investigate the role of renin secretion and of ACTH on the circadian rhythm of plasma aldosterone (PA), plasma renin activity (PRA), plasma cortisol (PC) and PA were determined at short-time intervals in 10 normal supine men. Six subjects were studied under a normal sodium intake and 4 under sodium restriction. In 4 subjects the secretion of ACTH was suppressed by dexamethasone.
Under normal sodium intake changes in PA seemed to be more in parallel with changes in PC than by those in PRA as indicated by a higher significant correlation between PA and PC than between PA and PRA in 3 of the 4 subjects. In 1 subject no correlation was observed between PA and PC despite visual synchronism between the plasma concentrations of both hormones. Under dexamethasone medication fluctuations in PA were followed by those in PRA while PC was less than 2 μg/100 ml. In the sodium restricted state, changes in PA were closely paralleled and significantly correlated to PRA while no correlation was seen between PA and PC. Under dexamethasone medication the significant correlation between PA and PRA persisted.
Our results indicate that in normal supine man the influence of ACTH and renin on PA may vary with different sodium intakes.
Under normal sodium intake ACTH seems to be the dominant factor controlling PA, whereas under sodium restriction changes in PA are mediated through the renin angiotensin system.
When the secretion of ACTH is suppressed by dexamethasone, renin controls PA both under normal and low sodium intake.
ADRENAL POTASSIUM AND SODIUM IN EXPERIMENTAL HYPER- AND HYPOALDOSTERONISM IN THE RAT. DETERMINATION BY ELECTRON PROBE X-RAY MICROANALYSIS
Authors: Szalay Katalin Sz. , Bácsy Ernö , Stark Ervin 
Published: December 2008

ABSTRACT
Potassium and sodium contents in the various adrenal zones were determined in experimental hyper- and hypoaldosteronism in the rat by electron probe X-ray microanalysis. The analysis aimed at revealing intracellular values.
There was no change in the potassium content of the zona glomerulosa, zona fasciculata and medulla neither in hyperaldosteronism, induced by Na-deficiency, nor in hypoaldosteronism, elicited by Na-rich diet. The sodium content in the zona glomerulosa and zona fascicularis was increased in the Na-loaded rats, while that of the medulla was not changed.
Our data are not consistent with the hypothesis that a change of adrenal intracellular potassium would act as a final stimulus in the regulation of aldosterone secretion.
IDENTIFICATION AND QUANTITATIVE DETERMINATION OF STEROIDS IN BOVINE CORPUS LUTEUM DURING OESTROUS CYCLE AND PREGNANCY
Authors: Axelson M. , Schumacher G. , Sjövall J. , Gustafsson B. , Lindell J. O. 
Published: December 2008

ABSTRACT
Neutral steroids in bovine corpus luteum were isolated by liquid-gel chromatography on hydrophobic Sephadex, and were analyzed by computerized gas chromatography-mass spectrometry. The presence of progesterone and 20β-hydroxy-4-pregnen-3-one was confirmed. In addition, 3β- hydroxy- 5- pregnen -20- one, 5- pregnene- 3β,20β -diol, 3β-hydroxy-5α-pregnan-20-one and 5α-pregnane-3β,20β-diol,32 were fully identified, and 3-hydroxy-4-pregnen-20-onne, 4 pregnene-3,20-diol, 22-hydroxycholesterol and 20,22-dihydroxycholesterol were partially characterized. Steroid sulphates were not detected.
Quantification of the six fully identified steroids was based on peak areas in specific fragment ion current chromatograms constructed by the computer. During the 4th–19th day of the oestrous cycle the steroid concentrations varied as follows: progesterone 6.0–36.7 μg/g wet luteal weight, 20β-hydroxy-4-pregnen-3-one 0.8–5.5 μg/g, 3β-hydroxy-5-pregnen-20-one 1.0–7.1 μg/g, 5-pregnene-3β,20β-diol < 0.2–0.9 μg/g, 3β-hydroxy-5α-pregnan-20-one 1.7–8.6 μg/g, and 5α-pregnane-3β,20β-diol < 0.2-1.2 μg/g.
The concentrations of progesterone and 3β-hydroxy-5-pregnen-20-one seemed to vary in parallel and were low during days 11–17. During this period the concentrations of 5-pregnene-3β,20β-diol and 5α-pregnane-3β,20β-diol were highest as was the relative contribution of all three 20β-hydroxysteroids to the total amount of steroids. The relative amount of 3β-hydroxy-5α-pregnan-20-one seemed to be highest during days 4–6.
The total steroid concentration in corpora lutea taken in early pregnancy (75–105 days) was 18–47 μg/g. In the period 75–90 days, progesterone constituted only 35–42 % of the total steroids, 3β-hydroxy-5α-pregnan-20-one as much as 23–40 % and the total 20β-hydroxysteroids 18–30%. The total steroid concentration in corpora lutea taken in midterm and late pregnancy was 21–77 μg/g. In this period progesterone was by far the predominant steroid and constituted about 80–90 % of the total steroids in corpora lutea taken between days 150 and 240.
Possible correlations between luteal growth, steroid oxidoreductases and steroid concentrations are discussed.
THE EFFECT OF OESTRADIOL-3N-BIS-(2-CHLOROETHYL)CARBAMATE-17β-PHOSPHATE (ESTRACYT®) ON THE 5α-REDUCTASE IN THE RAT VENTRAL PROSTATE
Authors: Høisaeter Per Aage 
Published: December 2008

ABSTRACT
The ventral prostate of the rat both after in vitro incubation and in vivo experiments was found to contain appreciable 5α-reductase activity, whilst a very low activity was registered in the diaphragm and liver. Neither Estracyt® nor LEO275 (Estracyt® without the phosphate group in position 17 of the oestradiol moiety) had an inhibitory effect on the enzyme activity after in vitro incubation but equivalent amounts of oestradiol-17β and oestradiol-17β-phosphate significantly reduced 5α-reductase activity. When Estracyt® was injected in vivo no influence on activity was registered in "short term" experiments while a significant inhibition was found after "long term" treatment in vivo. Possible explanations for this "long term" effect of Estracyt® on 5α-reductase activity are discussed.
THE ULTRASTRUCTURE OF THE ACCESSORY SEX ORGANS OF THE MALE RAT
Authors: Dahl Erik , Hars Renate 
Published: December 2008

ABSTRACT
The present paper describes the fine structure of the accessory sex organs of the male rat as seen after administration of the anti-androgenic compound chlormadinon acetate for 20 days. There was a general involution of the organs with macroscopic atrophy and reduced amount of secretory material. Ultrastructurally the cells contained less organelles as compared with the controls, loss of cytoplasm and reduction both of cell height and width. The major changes also included reduction of the Golgi areas and the rough endoplasmic reticulum. Within the dorsal lobe prominent nuclear changes were found. The alterations observed in the present study are similar to the changes which were found in rats treated with another anti-androgenic compound, Cyp A. It is concluded that these two anti-androgenic compounds exert their effects through similar mechanisms with a specific influence on the prostate and the seminal vesicles.
PURIFICATION AND CHARACTERISATION OF TWO PORCINE HYPOTHALAMIC FRACTIONS WITH LH-RELEASING ACTIVITY: EVIDENCE FOR A SINGLE LH AND FSH-RELEASING HORMONE
Authors: Sandow J. , Enzmann F. , Arimura A. , Redding T. W. , Schally A. V. 
Published: December 2008

ABSTRACT
Two fractions with LH releasing activity were obtained from porcine hypothalami by Enzmann et al. (1972). These fractions were designated E 57 and E 203. By comparison with pure natural LH-RH and synthetic LH-RH, E 203 was identified as purified natural LH-RH. E 57, which has only 25 % of the activity of E 203, was further evaluated for its biological and immunological activity. E 57 has the same ratio of LH/FSH-releasing activity as natural LH-RH. The binding to a specific LH-RH antiserum is identical with that of natural LH-RH and E 203. It is concluded, that E 57 is an artifact of isolation derived from natural LH-RH. These findings can be considered as additional evidence for the identity of the hypothalamic LH and FSH releasing hormone, since both gonadotrophins are stimulated by the two hypothalamic fractions.
THE EFFECT OF APOMORPHINE ON BASAL AND TRH STIMULATED RELEASE OF THYROTROPHIN AND PROLACTIN IN MAN
Authors: Nilsson Karl Olof , Wide Leif , Hökfelt Bernt 
Published: December 2008

ABSTRACT
Studies were performed in two groups of healthy male volunteers to evaluate the effect of apomorphine on the secretion of thyrotrophin (TSH) and prolactin under basal conditions and following the administration of thyrotrophin releasing hormone (TRH).
Apomorphine HCl, administered sc in a dose of 0.75 mg had no effect on the basal levels of plasma TSH or serum prolactin.
The iv injection of 200 μg TRH was followed by an increase in TSH and prolactin in all subjects, with a maximum 20–30 min after the injection. When 0.75 mg of apomorphine was injected sc 30 min before TRH, the increase in prolactin was significantly reduced whereas the TSH response was unaltered.
Our studies indicate that the TRH induced secretion of prolactin in man can be suppressed through a dopaminergic mechanism whereas the secretion of TSH is not influenced.
PITUITARY HORMONES IN WOMEN WITH CHRONIC RENAL FAILURE: THE EFFECT OF CHRONIC INTERMITTENT HAEMO-AND PERITONEAL DIALYSIS
Authors: Ølgaard K. , Hagen C. , McNeilly A. S. 
Published: December 2008

ABSTRACT
Measurements of plasma prolactin (hPr), growth hormone (HGH), thyrotrophin (TSH), luteinizing (LH) – and follicle stimulating hormone (FSH) were performed in 20 women with chronic renal failure on regular dialysis. There was no significant difference in any of the hormone levels before and after the dialysis and no significant influence of the type of dialysis (haemodialysis and peritoneal dialysis) or the time of dialysis. Higher levels of plasma prolactin was found in the women on peritoneal dialysis than in the haemodialyzed women presumably due to the medical treatment.
In the peritoneally dialyzed group four women had irregular menstruations and normal gonadotrophic levels, but elevated hPr and it is suggested that this finding is similar to that seen in the amenorrhoeagalactorrhoea syndrome, where hPr presumably in some way have anti-gonadotrophic actions at the gonadal level.
ACUTE EFFECTS OF EXOGENOUS GROWTH HORMONE IN MAN: TIME- AND DOSE-BOUND MODIFICATION OF GLUCOSE TOLERANCE AND GLUCOSE-INDUCED INSULIN RELEASE
Authors: Adamson Ulf , Cerasi Erol 
Published: December 2008

ABSTRACT
The time and dose dependency of the effects of a 30-min long iv infusion of human growth hormone (GH) on glucose tolerance and glucose-stimulated insulin release was investigated in 19 healthy subjects. Glucose tolerance deteriorated immediately following GH, and the k-value continued to decrease up to 300 min later. A small but significant reduction of glucose tolerance persisted 24 h after GH administration. Significant deterioration of glucose tolerance was observed with the smallest GH dose used (5 μg per kg body weight), increasing the amount of the hormone having no further major influence.
Glucose-stimulated insulin release was significantly inhibited 1 h after administration of a relatively high GH dose (40 μg per kg), both if expressed as mean plasma insulin levels, or as insulin release per magnitude of glucose stimulation (insulinogenic index). In the majority of subjects, insulin release was inhibited also by lower GH doses (5–20 μg GH per kg). However, the mean change with these doses was not statistically significant. The inhibitory effect of GH on insulin secretion seemed to have a duration of several hours. Five hours, but not 24 h, after GH administration (10 μg GH per kg) insulin release was still significantly suppressed.
It is suggested that the initial effect of GH on pancreatic beta cells may be inhibition of insulin release, in contrast with the enhancement of insulin secretion observed during chronic administration of GH.
SYNTHETIC HUMAN CALCITONIN: ANALYSIS OF ANTIBODIES OBTAINED FROM VARIOUS ANIMAL SPECIES AND DETERMINATION OF IMMUNOREACTIVE HORMONE IN HUMAN SERA
Authors: Dietrich F. M. , Hunziker W. H. , Fischer J. A. 
Published: December 2008

ABSTRACT
Antibodies to synthetic human calcitonin (hCT) were developed in rabbits, goats and mice. The free peptide (32 amino-acid residues, Mwt. 3418) was administered together with adjuvant, and the effect of various immunization procedures, as well as of different dose-levels, was evaluated comparatively. Synthetic hCT was found to be a good immunogen for the three animal species examined. The relative importance of various structural parts of the hCT molecule with regard to immunological specificity was determined by reference to the inhibition of the specific binding of 125I-hCT to antibodies by peptide fragments of hCT. All the antisera studied were directed to structural and/or conformational properties of the 11–28 or 11–32 amino acid sequence of hCT. Six different antisera from rabbits and goats were selected for radioimmunological assay of hCT on the basis of their inhibitory dose50-values and immunological specificity. To improve the sensitivity of the radioimmunoassay (RIA), we studied the preparation of radioiodinated hCT and assessed various parameters determining the sensitivity of the assay. Despite all the efforts, CT in human plasma from healthy subjects could not be determined with certainty. The difficulties encountered in the determination of normal levels of circulating CT are discussed in terms of the sensitivity of RIA and non-specific interference of serum factors with RIA.