bluuebunny/crossref_metadata_2025_split huggingface dataset:
MULTICOMPONENT GAS CHROMATOGRAPHIC ANALYSIS OF URINARY STEROIDS EXCRETED BY AN INFANT WITH A DEFECT IN ALDOSTERONE BIOSYNTHESIS
Authors: Shackleton C. H. L. , Honour J. W. , Dillon M. , Milla P. 
Published: December 2008

ABSTRACT
The urinary steroids excreted by an infant with a salt-wasting syndrome due to a suspected defect in the 18-oxidation of corticosterone have been analysed by gas chromatography-mass spectrometry. The excretion of tetrahydroaldosterone was low (3.5 μg/24 h) whilst the excretion of 3α, 11β,21-trihydroxy-5α-pregnan-20-one (allo-tetrahydrocorticosterone) and other corticosterone metabolites was high (total about 2 mg/24 h). The excretion of cortisol metabolites was apparently normal for age (total about 2 mg/24 h) but 3α,11β,17α,21-tetrahydroxy-5α-pregnan-20-one (allo-tetrahydrocortisol) rather than tetrahydrocortisone, was the major component of the group.
The excretion of an 18-hydroxycorticosterone metabolite 3α,18,21-trihydroxy-5β-pregnane-1 1,20-dione (18-hydroxytetrahydroCompound A) was higher than normal for infants of this age (between 50 and 200 μg/24 h), suggesting that the defect was in 18-hydroxysteroid dehydrogenase rather than 18-hydroxylase. In addition, 18-hydroxytetrahydrocorticosterone, another metabolite of 18-hydroxycorticosterone was tentatively identified and it was found that the rate of excretion of this compound was of similar magnitude to 18-hydroxytetrahydroCompound A.
The salt balance of the infant has been successfully controlled by salt administration (77 mEq./24 h) and treatment with Fludrocortisone (0.5 mg/day).
RELATIONSHIP BETWEEN OESTROGEN, PROSTAGLANDIN F2α AND HISTAMINE IN DELAYED IMPLANTATION IN THE MOUSE
Authors: Saksena S. K. , Lau I. F. , Chang M. C. 
Published: December 2008

ABSTRACT
Treatment of pregnant mice ovaricctomized on day 3 (23.00-2330 h) with progesterone (1 mg/day/mouse, from day 4 through 11 post coitum (p.c.)) and oestrogen (single injection of 0.05 αg on day 8 p. c.) induced implantation in all the animals. Implantation was inhibited in animals following three subcutaneous injections of indomethacin given on the morning and afternoon of day 8 and the morning of day 9 p. c. A single injection of histamine on day 8 p. c. partially compensated the effect of indomethacin. A complete reversal of the antifertility effect of indomethacin was achieved following intraperitoneal administration of histamine (2 αg at noon of day 8 p. c.) and PGF2α (20 μg on the morning and afternoon of day 8 p. c.). This study suggests that in the mouse uterus indomethacin impairs the physiological changes which are required for the decidual cell formation and implantation. It is likely that an injection of oestradiol in the progesterone treated ovariectomized mice triggers the release of PGF2α and histamine and that these compounds are involved in the chain of events leading to implantation of the blastocysts.
UTILIZATION OF DEHYDROEPIANDROSTERONE AND ITS SULPHATE FOR OESTROGEN PRODUCTION BY PREGNANT BABOONS (Papio papio)
Authors: Townsley John D. 
Published: December 2008

ABSTRACT
The effect of varying maternal circulating 3β-hydroxy-5-androsten-17-one (D) and its sulphate (DS) on urinary oestrogen (Oe) excretion by baboons was determined between 65 and 174 days gestation (term = 184 days). Oe (mainly oestrone) was determined by radioimmunoassay after enzymic hydrolysis of conjugates. Increments in Oe were estimated from the difference between Oe during 5 days pre- and post-treatment. Oestradiol-17β (5 mg in 5.0 ml saline-ethanol, 1:1) administered iv increased (P < 0.001) Oe by 2.46 ± 0.71, 7 (mean, mg ± sd, number of experiments). The response to 100 mg D (3.20 ± 1.50, 7) was greater (P < 0.001) than that due to 100 mg DS (0.03 ± 0.75, 7). The response to DS was not different from that due to saline-ethanol alone (-0.05 ± 0.27, 5). Betamethasone (9α-fluoro-11β,17,21-trihydroxy-16β-methyl-1,4-pregnadiene-3,20-dione) administration (3 mg bi-daily, im) caused an approximately 90% reduction in Oe within 4 days. In animals treated chronically with betamethasone the response due to 100 mg D (2.74 ± 1.04, 5) was again greater (P < 0.001) than that due to 100 mg DS (0.10 ± 0.09, 5). ACTH (8 U or 40 U, im, N = 11) produced a variable but not significant mean change in Oe at either dose level. Metyrapone (300 mg every 4 h for 6 doses) increased (P < 0.005) Oe (0.77 ± 0.48, 5). It is concluded that in normal pregnant animals and those treated with betamethasone, in which endogenous levels of D and DS are presumably reduced, D is preferentially used over DS for oestrogen production. Variations in DS availability do not produce marked changes in oestrogen production. This suggests that rapid increases in oestrogen production, as occur for example close to term, may result from increased availability of D rather than DS. The variable responses to ACTH and the increase in Oe following metyrapone administration are compatible with significant foetal contributions of oestrogen precursors, the production of which is under ACTH control.
INFLUENCE OF SUCKLING AND OF SUCKLING FOLLOWED BY TRH OR LH-RH ON PLASMA PROLACTIN, TSH, GH AND FSH
Authors: Jeppsson S. , Nilsson K. O. , Rannevik G. , Wide L. 
Published: December 2008

ABSTRACT
Ten women were studied during the first post-partum week. Suckling for 20 min induced a marked increase in plasma prolactin, reaching a maximum within 0–25 min after the end of suckling and then returning to pre-suckling levels after 120 min. Suckling induced no changes in plasma thyrotrophin (TSH), growth hormone (GH) or follicle stimulating hormone (FSH). The iv injection of 200 μg of thyrotrophin releasing hormone (TRH) immediately after suckling resulted in an additional increase in plasma prolactin and a rise in TSH. When given 120 min after suckling TRH was followed by increased plasma levels of prolactin and TSH, which for both hormones were of a magnitude comparable to the TRH induced increment seen immediately after suckling. Thus, suckling did not inhibit the effect of TRH on the release of TSH. These studies indicate that TRH is probably not involved in the suckling induced increase in prolactin secretion.
The mean plasma FSH level was below the limit of detection before and after suckling. Neither plasma FSH nor prolactin showed any appearant changes following the iv injection of 25 μg of luteinizing hormone releasing hormone (LH-RH), when given immediately after and 120 min after suckling.
When given after suckling as indicated above, TRH induced no changes in plasma GH or FSH and similarly LH-RH was without influence on plasma GH and TSH.
RADIOIMMUNOASSAY OF RAT PROLACTIN AND ITS USE IN MEASURING PROLACTIN PRODUCTION BY CULTURED PITUITARY CELLS
Authors: Haug E. , Gautvik K. M. 
Published: December 2008

ABSTRACT
A sensitive and specific radioimmunoassay has been developed for rat prolactin (rPRL), employing the double antibody solid phase technique for the separation of free and antibody-bound [125I]rPRL. The anti-serum was raised in rabbits and showed no cross-reaction with rat growth hormone (rGH), follicle stimulating hormone (rFSH), luteinizing hormone (rLH) and thyrotrophin (rTSH). The immunosorbent (sheep anti-rabbit IgG bound to cellulose) showed a surprisingly high binding of [125I]rPRL, but not of the other iodinated anterior pituitary hormones. Addition of serum to the incubation mixtures prevented the binding between [125I]rPRL and the immunosorbent. Three different clonal strains of pituitary cells have been examined for production of rPRL, rLH and rTSH, both in the basal state as well as after treatment with thyrotrophin releasing hormone (TRH) and gonadotrophin releasing hormone (LH/FSH-RH). Monolayer cultures of two of the cell strains produced and secreted rPRL spontaneously, and they showed a 2-fold increase in rPRL production after treatment with TRH (3·10−7 mol/1). The third cell strain did not produce rPRL spontaneously, or after treatment with TRH. None of these cell strains could be stimulated to produce rTSH by treatment with TRH. Treatment of the same three cell strains with LH/FSH-RH (1.2·10−6 mol/1) failed to induce production of rLH, and there were no changes in production of rPRL. Prostaglandins E1 and E2 (3·10−8 mol/1) and oestradiol-17β (10−7–10−10 mol/1), however, stimulated the production of rPRL. The effects of TRH and prostaglandins E1 and E2 were observed within 24 h of treatment, while the first effect of oestradiol-17β was seen after 3 days. These results suggest that the stimulatory effect of oestradiol-17β on rPRL production differs from that of TRH and prostaglandins.
STUDIES ON THE MECHANISM OF ACTION OF POTASSIUM IODIDE ON THYROID PROTEIN BIOSYNTHESIS
Authors: Pisarev Mario A. , Aiello Leonardo O. 
Published: December 2008

ABSTRACT
Potassium iodide (KI) has been shown to have an antigoitrogenic action and to inhibit in vivo thyroid protein biosynthesis. Beef thyroid slices were used to clarify further the mechanism of action of KI. Incubations were performed in Krebs-Ringer-bicarbonate (KRB) buffer under 95% O2 and 5% CO2. KI caused a slight decrease in the uptake of [3H]leucine by the tissue. When labelled leucine incorporation into protein was measured it was found that 10−6 m KI caused a marked inhibition. Increasing concentrations of KI up to 10−3 m did not further increase this inhibition. This effect of KI was reduced by simultaneous addition of 0.5 mm KClO4 or 1 mm methylmercaptoimidazole (MMI). In several experiments it was found that equimolar amounts of thyroxine (T4) or triiodothyronine (T3) were more potent than KI in inhibiting thyroid protein biosynthesis.
In double labelled studies KI decreased [3H] leucine incorporation into thyroid soluble proteins and into immunoprecipitable thyroglobulin (Tg) while it did not modify that of [14C]galactosamine.
When tissue specificity was examined, KI failed to alter [3H] leucine incorporation into proteins either in the liver or in the submaxillary gland. The present results indicate that intracellular KI is necessary to exert its effect on protein synthesis, and that this effect is mediated through a organic form of iodine, probably iodothyronines. This action of KI is specific for the thyroid gland.
DRUG CONTROL OF CUSHING'S SYNDROME
Authors: Child D. F. , Burke C. W. , Burley D. M. , Rees Lesley H. , Fraser T. Russell 
Published: December 2008

ABSTRACT
Eighteen patients with Cushing's syndrome (16 pituitary-dependent Cushing's disease, 1 ectopic ACTH syndrome, 1 primary adrenal adenoma) were given a combination of aminoglutethimide and metyrapone, with the object of controlling cortisol overproduction using less toxic doses than would be required with each drug alone. A preliminary trial of this combination using doses of aminoglutethimide of 1 g or more a day was assessed over 2 weeks. Control of cortisol overproduction and clinical improvement was achieved but side effects led to withdrawal of the drugs in 6 out of the 12 patients. A lower dose trial of this combination over 2 weeks, using 750 mg/day of aminoglutethimide also controlled cortisol overproduction and side effects led to drug withdrawal in only 2 out of 6 patients. Four of these patients were successfully controlled with even lower doses (500-750 mg/day of aminoglutethimide) for longer periods (26 days–1 year). This low regimen which consists of aminoglutethimide 500–750 mg daily, metyrapone 2 g daily, dexamethasone 0.5 mg b. d. and fludrocortisone 0.1 mg daily, is useful for preparing patients for operative treatments and may be used as a long-term treatment of milder cases.
UPTAKE AND METABOLISM OF SEROTONIN BY RAT ADRENAL TISSUE IN VITRO
Authors: Trost Bernhard N. , Müller Jürg 
Published: December 2008

ABSTRACT
After incubation of separate zones of rat adrenals with radioactively labelled serotonin - at concentrations at which the amine had been previously shown to stimulate aldosterone biosynthesis - the tissue radioactivity was several times higher in the capsular ("zona glomerulosa") than in the decapsulated portions of the glands. High doses of unlabelled serotonin diminished the accumulation of radioactivity, but only when added simultaneously with the tracer. In the course of the incubation, radioactive 5-hydroxy-3-indoleacetic acid, i. e. the deaminated metabolite of serotonin, rapidly appeared in the medium. Most of the radioactive material accumulated by the adrenal was recovered in the cytosol fraction and was no longer identical with serotonin, but consisted mainly of 5-hydroxy-3-indoleacetic acid and another, unidentified metabolite. Unaltered serotonin was found in capsular adrenal tissue extracts only when a monoamine oxidase inhibitor (nialamide) had been added to the incubation medium. Rapid uptake and metabolism thus appeared to be the predominant features of the interaction of incubated adrenal tissue with serotonin. These events may have obscured the possible binding of very small amounts of serotonin to receptor sites. The observed accumulation of radioactivity in adrenal tissue was mainly due to delayed outflow of intracellularly formed metabolite, since 5-hydroxy-3-indoleacetic acid was neither taken up by incubated adrenals nor bound by adrenal cytosol. No evidence of serotonin storage in the zona glomerulosa was found in these studies.
OVARIAN BIOCHEMICAL COMPETENCE FOLLOWING GONADOTROPHIC DEPRIVATION FROM BIRTH
Authors: Kraiem Z. , Eshkol A. , Lunenfeld B. , Ahrén K. 
Published: December 2008

ABSTRACT
Normal ovarian morphogenesis is impaired by the absence of gonadotrophic hormones from birth. In the present study, the following question was asked: Does gonadotrophic deprivation also affect ovarian biochemical competence?
Newborn mice were treated daily with an antiserum neutralizing endogenous circulating gonadotrophins. At the age of 14 days, ovaries from these mice and control littermates were incubated in the presence and absence of gonadotrophic preparations; cAMP and lactic acid levels were then measured in tissue and incubation medium. Ovaries from antigonadotrophin treated and control mice had the same basal levels, per mg tissue, of cAMP and lactic acid. Moreover, the levels increased to approximately the same extent following in vitro gonadotrophic stimulation: an increase in cAMP of 8–10-fold (using a preparation with an hLH:hFSH ratio of 1:1) or 2½-fold (using a preparation with an hLH:hFSH ratio of 1:5), and about a 2-fold increase in lactic acid (using oLH).
The acute effect of gonadotrophins on ovarian glycolysis, reported up till now only in the rat ovary, is the first such demonstration in mice. The results also indicate that despite impaired morphogenesis, the enzymatic systems necessary for ovarian glycolysis (as measured by lactic acid production) and cAMP formation can develop without gonadotrophic participation. Furthermore, ovarian capacity to respond to hormonal stimulation is acquired post-natally, as shown by refractoriness to gonadotrophic stimulation during the first week of life. Finally, post-natal gonadotrophic exposure does not seem an essential requirement, at least as measured by the above parameters, for acquiring ovarian competence to respond to hormonal stimulation.
SERUM 5α-DIHYDROTESTOSTERONE AND TESTOSTERONE CHANGES WITH AGE IN MAN
Authors: Lewis J. G. , Ghanadian R. , Chisholm G. D. 
Published: December 2008

ABSTRACT
Serum 5α-dihydrotestosterone (DHT) and testosterone (T) were measured in 98 normal adult men aged between 20–80 years, separating T and DHT by thin layer chromatography and using a sensitive and reliable radioimmunoassay. In three age groups between 20–40, 40–60 and 60–80, the means ± sem for serum DHT were 84 ± 4, 79 ± 3 and 67 ± 3 (ng/100 ml) respectively. The corresponding values for testosterone were 559 ± 25, 491 ± 25 and 475 ± 28 (ng/100 ml). A significant decrease was observed in the DHT level of the 60–80 years age group compared to either the 20–40 (P < 0.01) or the 40–60 (P < 0.02) age groups. There was a moderate decline in the testosterone level of the 60–80 years age group compared to 20–40 years (P < 0.05) but there were no significant changes in the testosterone levels between other groups.
SOMATOMEDIN A IN HUMAN SERUM, DETERMINED BY RADIORECEPTOR ASSAY
Authors: Takano K. , Hall K. , Ritzén M. , Iselius L. , Sievertsson H. 
Published: December 2008

ABSTRACT
Somatomedin A was determined by radioreceptor assay in serum from patients with various disorders. The mean values of somatomedin A in serum from 20 adult subjects, 21 patients with acromegaly, and 17 patients with hypopituitary dwarfism were 1.08 ± 0.08, 3.02 ± 0.33 and 0.44 ± 0.03 U/ml, respectively. In children below 2 years of age, low levels were found (mean 0.40 ± 0.04 U/ml). Normal levels were found in patients with Turner's syndrome and primary hypothyroidism, increased levels in uraemic patients, and decreased levels in Laron dwarfs.
STUDIES ON THE POSTPONED GROWTH HORMONE SECRETION FOLLOWING THE INFUSION OF SOMATOSTATIN
Authors: Lucke C. , Höffken B. , von zur Mühlen A. 
Published: December 2008

ABSTRACT
It is well known and also confirmed in this study that somatostatin (growth hormone inhibiting factor, GHIF) prevents the nocturnal GH secretion, as long as the peptide is infused. Following the infusion a rapid rise in GH levels is seen in sleeping subjects with peak values of 26.8 ± 9.7 ng/ml compared to 31.7 ± 4.7 ng/ml (± sem) in control nights.
Delayed GH peaks were seen even in the absence of slow wave sleep. No postponed GH rise was observed when subjects fell asleep again. These data demonstrate that the postponed nocturnal GH peak does not represent a rebound phenomenon to a previous trigger mechanism but is acutely sleep induced.
THE IMPORTANCE OF GROWTH HORMONE AND LIOTHYRONINE IN INDUCED HYPOCALCAEMIA IN HYPOPHYSECTOMIZED ANIMALS
Authors: Sørensen O. Helmer , Lund Birger , Kølendorf Klaus 
Published: December 2008

ABSTRACT
The resistance to hypocalcaemia induced by synthetic salmon calcitonin (SCT) was studied in intact and hypophysectomized rats. The recovery from hypocalcaemia was greatly impaired in the latter group, but this was normalised by small doses of purified human growth hormone (GH). The initial hypocalcaemic response to SCT was delayed in the hypophysectomized rats. This was not affected by treatment with GH, but normalised by substitution with liothyronine. We conclude that GH accelerates the recovery from hypocalcaemia in hypophysectomized animals, perhaps by a stimulation of parathyroid activity, while thyroid hormone accelerates the initial hypocalcaemic response to SCT, probably by restoring the reduced rate of bone resorption.
WHISKY: A NEW PROVOCATIVE TEST FOR CALCITONIN SECRETION
Authors: Dymling John F. , Ljungberg Otto , Hillyard Carmel J. , Greenberg Peter B. , Evans Imogen M. A. , MacIntyre lain 
Published: December 2008

ABSTRACT
Oral whisky is a potent stimulus of calcitonin secretion. Peak increments of immunoreactive calcitonin are observed within 15 min after the ingestion of 50 ml of whisky; the magnitude of the response is similar to that observed during a four-hour calcium infusion. This procedure has several advantages over standard methods of stimulating calcitonin release in patients at risk of developing medullary carcinoma of the thyroid, and this is shown by a study in a large family with familial chromaffinomatosis.
RECIPROCAL EFFECTS OF THYROXINE AND TRIIODOTHYRONINE ON THEIR DEIODINATION BY RAT TISSUES IN VITRO
Authors: Zaninovich Angel A. 
Published: December 2008

ABSTRACT
The reciprocal effects of loading doses of thyroxine (T4) or triiodothyronine (T3) on the deiodination of their 125iodine-labelled isotopes by rat muscle and liver homogenates were studied. In 21 experiments muscle homogenates deiodinated a mean 45.0 % of a tracer dose of [125I]T4 and 18.0% of [125I]T3. On addition of graded amounts of non-radioactive T4 or T3 the percentual deiodination of both labelled hormones progressively declined. This effect was significantly greater in homogenates incubated with non-radioactive T4, thus reflecting a stronger affinity of this hormone for muscle deiodinating sites. This correlate with the greater displacement of [125I]T3 as revealed by the percentage of recovered labelled hormone. In 18 experiments liver homogenates deiodinated a mean 14.6% of a tracer amount of [125I]T4 and 8.5% of [125I]T3. The addition of a T4- or a T3-load was followed by a smaller decrease in percentual deiodination of both labelled hormones as compared to muscle homogenates. Unlike the effects observed in muscle, the breakdown of [125I]T4 and [125I]T3 by liver homogenates was equally affected by similar amounts of stable T4 or T3. It is concluded that in the present in vitro system T4 and T3 share cellular sites of deiodination in rat muscle and liver and that, at least in muscle, which constitutes over one-half of the rat body weight T4 appears to be preferentially deiodinated.
THYROID PEROXIDASE ACTIVITY IN IODINE DEFICIENT RATS
Authors: Fragu P. , Nataf B. M. 
Published: December 2008

ABSTRACT
The evolution of peroxidase activity was followed during the course of iodine deficiency in the rat. The enzymatic activity was determined in vitro by oxidation of iodide or by iodination of bovine serum albumin using a peroxide-generating system.
An inverse relationship between the stable iodine content in the gland and the peroxidase activity is observed; this relation is not linear and the highest increase is found when the iodine content in the gland is below 5 μg per thyroid gland, at 35 days of the treatment.
In animals maintained on a low iodine diet, a triphasic effect on enzymatic activity is observed: early (10 and 20 days) and late (70 and 80 days) effects when the increase in peroxidase activity is 3 times higher than the increase in weight, DNA and total protein content; and an intermediar effect (between 20 and 70 days) when the peroxidase activity stays approximately at the same level. In any case, the enzymatic activity increases to a greater extent than do thyroid weight, and total protein and DNA content, suggesting that high cellular activity is due to a specific enzyme induction comparable to that we obtained recently in human sporadic goitre.
PLASMA INSULIN AND GROWTH HORMONE CONCENTRATIONS IN PREGNANT SHEEP I:
Authors: Hove Knut , Blom Anne Kristine 
Published: December 2008

ABSTRACT
Two or three foetal lambs regularly result in a varying degree of carbohydrate shortage in mother ewes in late pregnancy. We have investigated the correlation between plasma insulin, growth hormone and energy substrate concentrations in ewes 8 and 1 weeks before lambing.
Plasma growth hormone was fairly constant (2–3 ng/ml) throughout the 24-h cycle 8 weeks before parturition. Seven weeks later higher average levels and increased diurnal fluctuations were observed in 3 out of 4 multiparous ewes. The average post-absorptive insulin levels were reduced by 50 per cent during the same interval. Simultaneously decreased post-absorptive sugar and increased acetoacetate levels were observed. It is concluded that the hormonal adaptations to the increasing carbohydrate deficit in late pregnancy, especially among multiparous ewes, include:
a) reduced post-absorptive plasma insulin levels,
b) reduced insulin responses to feeding, and
c) increased levels of growth hormone in the plasma.
IN VITRO SYNTHESIS OF STEROIDS BY A FEMINISING ADRENOCORTICAL CARCINOMA: EFFECT OF PROLACTIN AND OTHER PROTEIN HORMONES
Authors: Millington D. S. , Golder M. P. , Cowley T. , London D. , Roberts H. , Butt W. R. , Griffiths K. 
Published: December 2008

ABSTRACT
The study describes the effects of ACTH, prolactin and other protein hormones on the synthesis and secretion of steroid hormones by tissue from a feminising adrenocortical carcinoma removed from a post-menopausal female. Steroid production by the tissue was determined by high resolutionmass fragmentography and by radioimmunoassay. Prolactin and ACTH stimulated the synthesis of oestrogens by the tissue whereas GH, LH and ACTH were more effective than prolactin in stimulating androgen synthesis. The effect of protein hormones, other than ACTH, on adenylate cyclase activity of this tumour tissue indicated a lack of specificity of the membrane receptor sites.