bluuebunny/crossref_metadata_2025_split huggingface dataset:
GROWTH HORMONE SECRETION IN HYPOPHYSECTOMIZED RATS WITH MULTIPLE PITUITARY TRANSPLANTS
Authors: RUBINSTEIN LIDIA , AHRÉN K. 
Published: December 2008

SUMMARY
The secretion of growth hormone from anterior pituitary transplants under the kidney capsule of gonadectomized and hypophysectomized male rats was investigated with special regard to the importance of the mass of functioning pituitary tissue. Body growth and mammary gland development after testosterone stimulation were studied.
In rats with the pituitary gland autotransplanted to the kidney capsule body growth was markedly reduced. After administration of testosterone a few groups of alveoli only were seen in the mammary glands.
Hypophysectomized rats with four pituitary transplants (an autotransplant and three homotransplants) under the kidney capsule showed slightly better body growth than rats with an autotransplanted hypophysis. When compared with rats with intact pituitary glands body growth was markedly reduced. Mammary gland development after testosterone stimulation was as poor in rats with four pituitary transplants as in rats with an autotransplanted hypophysis.
These results suggest strongly that the normal secretion of growth hormone is regulated by the hypothalamus and that the deficiency of growth hormone in rats with the pituitary gland transplanted remote from the brain is due mainly to a loss of 'specific' stimuli from the hypothalamus and not to a 'non-specific' reduction in the amount of functioning pituitary tissue.
THE EFFECT OF NUTRITIONAL STATUS AND THYROID FUNCTION ON THE METABOLISM OF OESTRADIOL
Authors: BROWN J. B. , STRONG J. A. 
Published: December 2008

SUMMARY
The urinary excretion of endogenous and exogenous oestrogens was studied in patients with disordered thyroid function, and in obese and non-obese patients without evident thyroid disease. Hypothyroid patients and obese patients converted a larger percentage of administered oestradiol-17β to urinary oestriol and a lower percentage to urinary oestrone than hyperthyroid patients and non-obese patients. The recovery of administered oestradiol as oestriol, oestrone and oestradiol in urine was the same in the hypothyroid, obese and non-obese patients but considerably lower in the hyperthyroid patients. Similar differences were found in the urinary excretion of endogenous oestrogens. The excretion of endogenous oestrogens varies with the weight of the patient; it was greater in the obese than in the non-obese. The findings indicate that the pathways of oestrogen metabolism are influenced by a number of the factors, including thyroid function, associated with the weight of the patient.
THE EFFECTS OF CALCIUM ON PROTEIN-BINDING AND METABOLISM OF ARGININE VASOPRESSIN IN RATS
Authors: SMITH M. W. , THORN N. A. 
Published: December 2008

SUMMARY
Hypercalcaemia produced in rats by the intravenous injection of calcium chloride, slowed the rate of disappearance of injected vasopressin from the blood circulation. 24% of the vasopressin injected appeared in the urine of hypercalcaemic rats compared with 7 % in control animals.
Vasopressin injected intravenously into control rats was distributed in a volume equal to the blood volume but when rats had been made hypercalcaemic, the theoretical volume of distribution was three to four times greater. Antidiuresis produced by injection of large doses of vasopressin into hydrated rats was little affected by changes in the blood concentration of calcium. Calcium chloride injected intravenously into hydrated rats resulted in a temporary antidiuresis.
Experiments in vitro with Sephadex G-25 showed that both ox neurophysin and rat serum protein bind vasopressin and that calcium interferes with the binding.
It is suggested that calcium can compete directly with vasopressin for acidic binding sites on proteins; that this can cause the release of vasopressin and alter the transport and possibly the rate of inactivation, of vasopressin.
PLASMA 17-HYDROXYCORTICOSTEROIDS AND 17-OXOSTEROIDS IN PATIENTS WITH BREAST CANCER AND IN NORMAL WOMEN
Authors: DESHPANDE N. , HAYWARD J. L. , BULBROOK R. D. 
Published: December 2008

SUMMARY
(1) 17-Hydroxycorticosteroids (17-OHCS) and 17-oxosteroids were measured in the plasma of normal women, patients with early breast cancer and in patients with advanced metastatic disease.
(2) The mean plasma 17-OHCS level was found to be normal in the early stages of the disease but was raised in the advanced disease. In both groups of patients the variance was significantly greater than in normal women.
(3) The mean plasma 17-oxosteroid level in both early and advanced breast cancer was not significantly different from the normal level but the variance was increased.
(4) There is a significant correlation between the plasma 17-OHCS and 17-oxosteroids in normal women which was not found in the cancer patients.
(5) In patients with advanced breast cancer, the levels of plasma 17-oxosteroids were significantly correlated with the amounts of 11-deoxy-17-oxosteroids found in the urine. There was no correlation between plasma and urinary 17-OHCS.
(6) The physiological significance of these findings is discussed.
STUDIES ON THE MECHANISMS OF NIDATION
Authors: BARNEA AYALLA , SHELESNYAK M. C. 
Published: December 2008

SUMMARY
The effects of cervical ganglionectomy and uterine sympathectomy on nidation were investigated in the female rat. Cervicectomy resulted in: (1) Cervical ganglionectomy, as confirmed by histological examination of the extirpated tissue which revealed ganglia and (2) post-ganglionic sympathectomy of the uterus, as revealed by an 80% reduction of uterine noradrenaline measured on the 4th post-operative day. Cervicectomy (cervical ganglionectomy plus sympathectomy), performed a month before mating did not prevent impregnation or nidation, but interfered with normal foetal development. However, the regularity of oestrous cycles after cervicectomy was altered in about 30% (8/23) of the animals. Cervicectomy performed on the 1st or 2nd day of pregnancy did not prevent nidation.
CORTICOSTEROIDOGENESIS IN THE FRESH WATER AND SALINE-MAINTAINED DUCK (ANAS PLATYRHYNCHOS)
Authors: DONALDSON E. M. , HOLMES W. N. 
Published: December 2008

SUMMARY
No differences were observed in the patterns of adrenal steroidogenesis in vitro by ducks maintained on fresh water or on a hypertonic salt solution.
Determinations in vivo of the biological half-life of corticosterone showed no significant difference between ducks maintained on or loaded with saline and fresh water controls.
An increase in the apparent volume of distribution of corticosterone was, however, observed in birds loaded with the salt solution after maintenance on fresh water or salt solution.
Estimations were made of the secretory rate of corticosterone in vivo. In the ducks maintained on the salt solution an increased adrenal weight was responsible for the enhanced secretory rate but ducks maintained on fresh water and loaded with saline secreted corticosterone at a higher rate per unit weight of adrenal.
The implications of the increased rate of corticosterone secretion are discussed in relation to the known dependence of nasal gland function in marine birds on a functional adrenal gland.
HISTOCHEMICAL DEMONSTRATION OF 20β-HYDROXYSTEROID DEHYDROGENASE
Authors: BAILLIE A. H. , CALMAN K. C. , FERGUSON M. M. , HART D. McK. 
Published: December 2008

SUMMARY
NAD-dependent 20β-hydroxysteroid dehydrogenase activity can be demonstrated histochemically using Nitro-BT. 20β-Hydroxysteroid dehydrogenase activity was found in the Leydig cells of human and mouse testis, in the zona fasciculata of the mouse adrenal and in the theca interna of the mouse ovary.
THE EFFECT OF PROLONGED FEEDING OF GOITROGENS ON THYROID FUNCTION IN RATS
Authors: BROADHEAD G. D. , PEARSON I. B. , WILSON G. M. 
Published: December 2008

SUMMARY
Graded doses of propylthiouracil, carbimazole, sulphadiazine, potassium perchlorate and potassium thiocyanate were fed to groups of rats under standardized conditions for 2 months. The rats were given 131I 24 hr. before they were killed, and the thyroid weight, the proportions of labelled iodoaminoacids, and the thyroidal iodine content were determined. All the goitrogens produced increase in thyroid size, reduction of thyroidal iodine content, and an elevation of the monoiodotyrosine: di-iodotyrosine (MIT:DIT) ratio. The tri-iodothyronine: thyroxine (T3: T4) ratio was usually increased. Irrespective of the antithyroid compound used, there was a close correlation between the decrease in thyroidal iodine content and the rise in the MIT:DIT ratio.
In further experiments, either thyroid stimulating hormone (TSH) or thyroxine were injected s.c. twice daily for 5 days. TSH decreased the MIT:DIT ratio and increased the amount of labelled T3. Thyroxine increased the MIT:DIT ratio and decreased the amount of T4.
It is suggested that when goitrogens were administered for a prolonged period, the pattern of 131I-labelling of iodoaminoacids was dependent on a balance between inhibition of synthesis caused by the goitrogen and stimulation due to TSH. There was increased production of the physiologically more economical T3 in an attempt to compensate for decreased thyroxine formation.
A COMPARISON OF CERTAIN RESPONSES OF THE VASCULAR SYSTEM OF RATS AFTER THE ADMINISTRATION OF PROGESTERONE AND OESTROGEN
Authors: FULLERTON ALICE , MORRISON J. F. B. 
Published: December 2008

SUMMARY
The effects of progesterone and oestrogens on vascular responses to oxytocin were studied in female rats. Like oestrogens, progesterone caused the appearance of a pressor response to oxytocin, and throughout pseudopregnancy oxytocin acted as a pressor substance. The pressor response to oxytocin was the same, whether progesterone and oestrogen were given singly or together. Eserine abolished the pressor response to oxytocin of rats in natural oestrus or animals treated with an oestrogen, but did not eliminate the pressor response after progesterone.
EXCRETION OF 6-OXYGENATED METABOLITES OF PROGESTERONE AND 5β-PREGNANE-3α,17α,20α-TRIOL DURING PREGNANCY
Authors: FOTHERBY K. , JAMES FRANCES , KAMYAB SORAYA , KLOPPER A. I. , WILSON G. R. 
Published: December 2008

SUMMARY
The excretion of pregnanediol, pregnanetriol and the 6-oxygenated metabolites of progesterone by fifteen women has been measured throughout pregnancy. During the first trimester the level of excretion of the 6-oxygenated metabolites varied from 0·4 to 2·2 mg./day and at the end of pregnancy the range was from 3·5 to 11·6 mg./day. During the last 6 weeks of pregnancy, pregnanediol excretion was relatively constant, whereas in seven of the patients the excretion of the 6-oxygenated metabolites continued to increase. Except at the end of pregnancy there was a close correlation between the 6-oxygenated metabolites and pregnanediol excretion. The results suggest that the 6-oxygenated metabolites and pregnanediol have the same precursor and that little, if any, of a 6-oxygenated progesterone is secreted during pregnancy.
There appears to be little increase in pregnanetriol excretion during pregnancy; six of the subjects showed a significantly higher excretion in the third trimester compared with the first trimester of pregnancy, but the values were not outside the normal range for non-pregnant subjects. The specificity of the method of Fotherby & Love (1960) for the estimation of pregnanetriol was examined when applied to pregnancy urine.
Between 1·1 and 2·4 % of administered progesterone was excreted as the 6-oxygenated metabolites. In only one of five subjects was pregnanetriol excretion increased after progesterone administration.
THE RESPONSE OF THE PITUITARY-ADRENAL SYSTEM TO A STRESSFUL STIMULUS: THE EFFECT OF CONDITIONING AND PENTOBARBITONE TREATMENT
Authors: BARRETT A. M. , STOCKHAM M. A. 
Published: December 2008

SUMMARY
Handling of intraperitoneal injections of saline, twice daily for 10 days, did not significantly affect the resting level of corticosterone in the plasma or the adrenals. The conditioning abolished the usual changes in corticosterone levels caused by further handling or injections, reduced the response to exposure to ether vapour and had no effect on the response to histamine. The effect of pentobarbitone on plasma and adrenal corticosterone concentrations was found to be dependent upon the state of the pituitary-adrenal system before administration. Pentobarbitone had no effect on the responses of the adrenal cortex to exogenous adrenocorticotrophin. The responses to ether vapour or histamine of normal rats and rats lightly sedated with pentobarbitone were not significantly different as judged by changes in plasma and adrenal corticosterone concentrations and adrenal ascorbic acid depletion. However, rats deeply anaesthetized with pentobarbitone gave responses indicative of a depression of pituitary-adrenal activity. The sites of action of pentobarbitone on the pituitary-adrenal system are discussed.
RESUMPTION OF LACTATION BY SUCKLING IN LACTATING RATS AFTER REMOVAL OF LITTERS
Authors: ÔTA K. , YOKOYAMA A. 
Published: December 2008

SUMMARY
Foster litters were given to lactating rats whose own litters had been removed 3, 5 or 9 days previously. Lactation was restored in all groups by this re-suckling procedure within a relatively short period. The restoration of lactation became more difficult as the interval between the removal of the original litters and the application of the foster litters increased.
Changes in the nucleic acid content of the mammary gland after re-suckling were investigated in the rats whose litters were removed for 3 days before re-suckling. Both the DNAP content of the gland and its weight increased steadily in proportion to the length of the period of re-suckling, so that a fairly constant DNAP concentration was maintained in the tissue. The RNAP content and the RNAP:DNAP ratio, on the other hand, increased abruptly at about the time when milk secretion was initiated by re-suckling. The DNAP content continued to increase even after the onset of restored milk secretion. These results suggest that milk secretion after re-suckling began before full restoration of the tissue structure and that growth of the glandular tissue took place concurrently with milk secretion.
THE COMPARATIVE CONTRACEPTIVE ACTIVITIES OF 10β-HYDROPEROXY-17α-ETHYNYL-4-ESTREN-17β-OL-3-ONE (SCH 10015) AND NORETHYNODREL
Authors: WATNICK A. S. , GIBSON J. , VINEGRA M. , TOLKSDORF S. 
Published: December 2008

SUMMARY
10β-Hydroperoxy-17α-ethynyl-4-estren-17β-ol-3-one (Sch 10015) was found to be less progestational than norethynodrel but equally potent as a contraceptive agent in rats. To prevent pregnancy in all the treated females, a minimum daily dose of 5 mg./kg. body weight (MPD 100) of either agent was required. At this dose, both agents had similar contraceptive mechanisms of action. They partially blocked the release of pituitary gonadotrophin and when given on the 2nd and 3rd day after coitus, i.e. after ovulation, prevented conception. Pituitary gonadotrophin inhibition is not considered to be the primary mechanism of contraception because significant numbers of rats ovulate when treated with the MPD 100 of either compound. It is concluded that the time of the primary contraceptive action of these agents at their respective MPD 100 is post-ovulatory.
It would appear from these experiments that classical progestational activity is not required for the contraceptive action of these drugs.
LEVELS OF OXYTOCIN IN THE JUGULAR VEIN BLOOD OF GOATS DURING PARTURITION
Authors: FOLLEY S. J. , KNAGGS G. S. 
Published: December 2008

SUMMARY
Oxytocin has been assayed in the jugular vein blood of goats during parturition; for comparison a few measurements were also made during pregnancy. The hormone was extracted from blood plasma by gel filtration, followed by lyophilization and then assayed in the lactating guinea-pig by the increase in intramammary pressure after intra-arterial injection.
No oxytocin could be detected in the blood during pregnancy and it was found in only one of eight goats studied during the first stage of labour. The hormone was present in appreciable quantities in blood taken during the second stage of labour, and in general, the concentration rose to a maximum when the head presented. In cases of twin births oxytocin was usually present in the blood during the birth of the second kid but at a concentration lower than during delivery of the first. After expulsion of the kid the blood oxytocin titre diminished rapidly, suggesting that secretion of oxytocin ceased as soon as the kid was born. In three experiments the total release of oxytocin during a considerable portion (2·7–11·0 min.) of the second stage labour was estimated as 223–726 m-u.
The results are consistent with the view that oxytocin is not essential for the induction of labour. Rather the hormone is released in response to stimuli arising from distension of the vagina and vulva, and by virtue of its contractile effect on the uterus assists parturition.
The half-life of intravenously injected oxytocin in the lactating goat was found to be 1 min. 22 sec. After storage of lyophilized blood extracts at −15° for 5 months milk-ejection activity had declined by only 27%.
HISTOCHEMICAL UTILIZATION OF 3α-, 6β-, 11α-, 12α-, 16α-, 16β-, 17α-, 21- AND 24-HYDROXYSTEROIDS
Authors: BAILLIE A. H. , CALMAN K. C. , FERGUSON M. M. , HART D. McK. 
Published: December 2008

SUMMARY
The histochemical utilization of 3α-, 6β-, 11α-, 12α-, 16α-, 16β-, 17α-, 21- and 24-hydroxysteroids in human and mouse testis, human placenta, mouse ovary and rat adrenal has been investigated using a coupling method and the tetrazolium salt, Nitro-BT. 3α-Hydroxysteroid dehydrogenase was present in the human Leydig cells and placental syntrophoblast, but there was little in rat adrenal zona fasciculata and in mouse ovary; the enzyme is NAD or NADP dependent. 6β-Hydroxysteroid dehydrogenase was present in human Leydig cells, mouse Leydig cells, placental syntrophoblast, ova, granulosa, theca interna, corpora lutea and interstitial tissue; it is NAD dependent. 11α-Hydroxysteroid dehydrogenase activity was very poorly developed, being NAD dependent and demonstrable only in human Leydig cells. 12α-Hydroxysteroid dehydrogenase could be demonstrated in some human Leydig cells; it was both NAD and NADP dependent. 16α-Hydroxysteroids were very poorly used by all the tissues surveyed. 16β-Hydroxysteroids gave an intense histochemical reaction with NAD in human Leydig and Sertoli cells, in placental trophoblast, in adrenal zonae glomerulosa, fasciculata and reticularis and in all ovarian tissues. 17α-, 21- and 24-hydroxysteroids were poorly utilized by human Leydig cells, but not by the other tissues. The first two were NAD dependent; 24-hydroxysteroid utilization was both NAD and NADP dependent.
The techniques used are believed to demonstrate specific hydroxysteroid dehydrogenases because of variations in pyridine nucleotide requirement and in the location in the tissues of different hydroxysteroid dehydrogenases. Moreover, stereoisomers of the same hydroxysteroid behave differently in this system. The role of steroid 5α- and 5β-dehydrogenases is discussed in connexion with the histochemical results.
EFFECTS OF ETHER ANAESTHESIA AND HAEMORRHAGE ON HORMONE STORAGE AND ULTRASTRUCTURE OF THE RAT NEUROHYPOPHYSIS
Authors: DANIEL A. R. , LEDERIS K. 
Published: December 2008

SUMMARY
Effects of ether anaesthesia with or without haemorrhage were investigated in the rat neurohypophysis in vivo and in vitro. Simultaneous observations were made on hormone release from, and the ultrastructure of, the same neural lobes.
Variable decreases in hormone content were found in the neural lobes of both anaesthetized, and anaesthetized and bled animals. A significant depletion of vasopressin (P < 0·01) occurred in the latter group when related to pressor activity/mg. wet neurohypophysial tissue.
Incubation of neural lobes removed after stimulation showed that the proportions of diffusible (free) vasopressin and oxytocin had increased. Haemorrhage under ether anaesthesia caused a significant increase in the amount of free vasopressin (P < 0·01), but not of oxytocin (P > 0·05).
Examination of control and stimulated rat posterior pituitaries with the electron microscope showed a loss of the electron-dense material from the elementary granules of the neurohypophysial nerve fibres, their swellings and their terminals after the neurones had been subjected to hormone releasing stimuli. It is suggested that disappearance of the electron-dense content of the hormone-carrying granules is not related to hormone content in the gland.
An increased number of small vesicles (250–600 Å) was observed in the nerve fibre swellings of the stimulated posterior pituitary. The distribution, origin and function of these small vesicles is discussed.
THE DIURNAL PATTERN OF PLASMA GROWTH HORMONE CONCENTRATION IN CHILDREN AND ADOLESCENTS
Authors: HUNTER W. M. , RIGAL W. M. 
Published: December 2008

SUMMARY
The diurnal pattern of plasma growth hormone levels has been investigated in nine children, without endocrinopathy, aged 8–15 yr., from whom blood samples were taken hourly during the day and 2-hourly at night.
Growth hormone was undetectable (< 1 μmg./ml.) during the first 2 hr. after meals but the levels rose thereafter to values many times higher than those found in adults. High values were consistently encountered during the night.
THE ISOLATION AND IDENTIFICATION OF EXTREMELY POLAR UNCONJUGATED STEROIDS IN HUMAN PREGNANCY URINE
Authors: DIXON W. R. , PENNINGTON G. W. 
Published: December 2008

SUMMARY
Three highly polar unconjugated Δ4-3-oxosteroids containing a 6β-hydroxyl group have been isolated from human pregnancy urine. They have been identified as 6β,17α,20β,21-tetrahydroxypregn-4-ene-3,11-dione (compound 3), 6β,11β,17α,20α,21-pentahydroxypregn-4-en-3-one (Compound 4c) and 6β,11β,17α,20β,21-pentahydroxypregn-4-en-3-one (Compound 4d). Two further steroidal compounds were found, but have not as yet been identified. The isolation procedure involved the use of thin-layer chromatography for purification of the crude urinary extracts and paper chromatography for the isolation of the individual steroids. Chemical transformations and spectroscopic analyses have been used for the identification of the individual compounds.
HYDROXYSTEROID DEHYDROGENASES IN THE HUMAN ADRENAL CORTEX
Authors: CALMAN K. C. , BAILLIE A. H. , FERGUSON M. M. , HART D. McK. 
Published: December 2008

SUMMARY
The histochemical utilization of 3α-, 3β-, 6β-, 11α-, 11β-, 12α-, 16α-, 16β-, 17α-, 17β-, 20α-, 21- and 24-hydroxysteroids by three normal adult human adrenal glands, two human foetal adrenal glands, three adrenals from patients with Cushing's syndrome and one adrenal adenoma are described.
The normal adult human adrenal showed high 16β-hydroxysteroid dehydrogenase activity in the zona glomerulosa. Activity restricted to the outer part of the zona fasciculata was recorded with 3α-, 3β-, 6β-, 11β-, 16α-, 16β-, and 17β-hydroxysteroids. The zona reticularis utilized 3α-, 3β-, 11β-, 16β- and 17β-hydroxysteroids less well than the zona fasciculata.
The adrenals of Cushing's syndrome showed activity only for 3β- and 16β-hydroxysteroid dehydrogenases; this activity was noted in all three zones. The activity pattern of the adrenal adenoma resembled that of the normal adult human adrenal except that greater activity for 16α-hydroxysteroid dehydrogenase was noted.
The foetal part of the human foetal cortex was extremely active, showing 3α-, 3β-, 6β-, 11β-, 12α-, 16α-, 16β-, 17β-, 20β- and 21-hydroxysteroid dehydrogenase activity. The definitive cortex behaved similarly to the adult gland and possessed 3α-, 3β-, 11β-, 16β- and 17β-hydroxysteroid dehydrogenases; some evidence of zoning of the definitive cortex was seen with the 16β-hydroxysteroid.
The relevance of these findings in the light of current knowledge of adrenal zonation is discussed.