bluuebunny/crossref_metadata_2025_split huggingface dataset:
INACTIVATION OF LONG-ACTING THYROID STIMULATOR IN VIVO
Authors: SMITH B. R. , MUNRO D. S. 
Published: December 2008

SUMMARY
The prolonged action of long-acting thyroid stimulator (LATS) in the McKenzie assay could be related to the slow clearance of LATS from the blood of assay mice.
Injection of soluble thyroid extracts before or after LATS reduced the assay response. This corresponded with the inactivation of circulating LATS activity by the formation of a complex which was then rapidly removed from the blood.
EFFECT OF SOME ANTI-OESTROGENIC RING METHYL-SUBSTITUTED STILBOESTROLS ON THE UPTAKE OF TRITIATED OESTRADIOL BY THE MOUSE VAGINA
Authors: CLARK E. R. , McCRACKEN ANNA M. 
Published: December 2008

SUMMARY
Intravaginal administration to ovariectomized mice of 2·5 μg of either 3,3′,5,5′,α,α′-hexamethylstilboestrol (structure V) or 3,3′,5,5′-tetramethyl-α,α′-diethylstilboestrol (structure VI) significantly depressed the retention by vaginal tissue of concomitantly administered [6,7-3H]oestradiol-17β (0·75 × 10−4 μg), but did not affect the absorption of oestradiol from the vaginal lumen. The antagonism was shown by subcellular fractionation studies on vaginal homogenates to occur in the nuclear fraction.
THE ACCUMULATION, RETENTION AND INTERACTION OF OESTRADIOL AND OESTRONE IN CENTRAL NEURAL AND PERIPHERAL TISSUES OF GONADECTOMIZED FEMALE RATS
Authors: LUTTGE W. G. , WHALEN R. E. 
Published: December 2008

SUMMARY
Adult female rats which had been ovariectomized and hysterectomized were given tritiated oestradiol or tritiated oestrone and killed 1, 2 or 4 h later. Several brain samples were taken including anterior hypothalamus, posterior hypothalamus, 'cerebral peduncle' and cerebral cortex. Pituitary and blood plasma samples were also taken. [3H]Oestradiol and [3H]oestrone showed different patterns of retention in basal brain structures. After [3H]oestradiol administration the anterior hypothalamus retained more radioactivity than the posterior hypothalamus, which in turn retained more radioactivity than the cerebral peduncle. With [3H]oestrone, samples from the cerebral peduncle and posterior hypothalamus retained more radioactivity than samples from the anterior hypothalamus. The cerebral peduncle and posterior hypothalamus did not differ from one another in this respect. After administration of either hormone, all basal brain structures retained more radioactivity than cerebral cortex and plasma. The pituitary retained six times more radioactivity after administration of [3H]oestradiol than after [3H]oestrone.
For ovariectomized females killed 2 h after the injection of [3H]oestradiol, pretreatment with oestradiol for 30 min reduced the radioactivity retained in the pituitary and anterior hypothalamus, while pretreatment with oestradiol for 24 h produced no changes in uptake except in the uterus where radioactivity levels were nearly doubled. The increased uterine uptake was independent of increases in uterine weight. Oestrone pretreatment failed to produce consistent effects except at high doses where it reduced [3H]oestradiol uptake in the pituitary and hypothalamus. Pretreatment with either oestrone or oestradiol had no effect on uptake by neural tissues after [3H]oestrone injection.
It is concluded that there are at least four kinds of oestrogen uptake mechanisms in the female rat. The uterus contains a limited capacity 'receptor system' which selectively accumulates oestradiol and which permits displacement of oestradiol by oestrogen post-treatment, and stimulation of oestradiol uptake by oestrogen pretreatment. In the pituitary, oestradiol is selectively accumulated by a limited capacity receptor system which permits oestradiol displacement, but not oestradiol uptake stimulation. The brain contains two receptor systems: a regionally localized limited capacity receptor system for the non-displaceable selective accumulation of oestradiol, and a regionally localized comparatively unlimited capacity receptor system for the selective accumulation of oestrone.
ELIMINATION OF RADIOIODINE BY THE SHEEP PAROTID GLAND AFTER [131I]l-TRI-IODOTHYRONINE ADMINISTRATION
Authors: ŚLEBODZIŃSKI A. 
Published: December 2008

SUMMARY
A study was made of the metabolism of [131I]l-tri-iodothyronine ([131I]T3), in sheep with a unilateral fistula of the parotid gland. After [131I]T3 injection a constant rise in radioactivity in the saliva and a decline in the radioactivity of the serum were found; detectable amounts of radioiodine reentered the circulation from the metabolized hormone after 1 h. Gel filtration showed that the radioactivity in the collected saliva was due to inorganic [131I]iodide. Such an effect might be caused by deiodination [131I]T3 which occurs in sheep parotid glands in vitro. The presence of tracer amounts of hormonal radioiodine in individual sheep could not be excluded.
Non-specific deiodinating enzymes may exist in sheep parotid salivary glands.
CHANGES IN GONADOTROPHINS, OVARIAN STEROIDS AND FOLLICULAR MORPHOLOGY IN SHEEP AT OESTRUS
Authors: BJERSING L. , HAY MARY F. , KANN G. , MOOR R. M. , NAFTOLIN F. , SCARAMUZZI R. J. , SHORT R. V. , YOUNGLAI E. V. 
Published: December 2008

SUMMARY
The concentrations of progesterone, oestrogen and luteinizing hormone (LH) in ovarian venous plasma, and of progesterone, follicle-stimulating hormone, LH and prolactin in peripheral plasma were measured in 47 Welsh Mountain sheep at accurately timed stages around oestrus. The histology and ultrastructure of the pre-ovulatory and newly ruptured follicles in these animals were also examined.
The highest ovarian vein levels of oestrogen were invariably obtained from the ovary containing the largest non-atretic follicle. A significant amount of oestrogen was already being secreted by day 13, when both the peripheral and ovarian venous blood progesterone levels were still high.
On day 15 the corpus luteum stopped secreting progesterone; coincident with this decline there was a maximal increase in oestrogen secretion from the largest non-atretic follicle. The thecal cells of this follicle enlarged concomitantly with the rise in oestrogen, and maximal development of the smooth endoplasmic reticulum was observed at or after the oestrogen peak.
By 6 h after the onset of oestrus, progesterone concentration was still very low, and oestrogen values had fallen in most animals, while LH showed a pronounced increase. The maximal level of prolactin was also found at this time.
By 15 h after the onset of oestrus, both progesterone and oestrogen values were low and LH had returned to baseline levels except in a few animals. Ovulation had occurred in 11 out of 12 animals by 30 h after the onset of oestrus and the recently ruptured follicle was just beginning to secrete a little progesterone. Luteinizing hormone and oestrogen values were very low.
INCREASED CHROMATIN ACID LABILITY AND ACTINOMYCIN-D BINDING IN ENDOMETRIAL CELLS UNDER THE ACTION OF SEX STEROIDS
Authors: LEROY F. , PREUMONT A. M. , GALAND P. , BRACHET J. 
Published: December 2008

SUMMARY
Modifications of chromatin activity, induced by sex steroids, were studied in rat endometrial tissues by the following semi-quantitative cytochemical methods: 'staining' of fixed uteri by [3H]actinomycin-D followed by radioautography and cytophotometric evaluation of Feulgen reaction kinetics in isolated endometrial nuclei. The following hormonal treatments were applied to groups of animals: oestradiol-17β (10 μg); progesterone (2 mg); progesterone (2 mg daily for 4 days) with oestradiol-17β (0·05 μg on the 4th day). With both cytochemical methods, different hormonal treatments were found to induce different patterns of response in endometrial cell types. In luminal epithelium and endometrial stroma, hormonal treatment increased the binding of actinomycin-D in a variable manner as judged from autoradiographic grain counts. Sex steroids also induced an overall increased DNA acid-lability as estimated by cytophotometric evaluation of Feulgen staining intensity. Hormonal treatments induced different hydrolysis curve patterns in both endometrial nuclear types.
CORTICOTROPHIN-INDUCED DIFFERENTIATION OF MITOCHONDRIA IN RAT ADRENAL CORTICAL CELLS GROWN IN PRIMARY TISSUE CULTURE: EFFECTS OF ETHIDIUM BROMIDE
Authors: MILNER A. JOSEPHINE 
Published: December 2008

SUMMARY
Foetal rat adrenals were grown in primary tissue culture. The effects of ethidium bromide on the adrenocorticotrophin (ACTH)-induced differentiation of the mitochondria of the cortical cells were examined. Ethidium bromide (1 μg/ml/day for 4 days) inhibited the morphological transformation of the mitochondria normally induced by ACTH. At the same time the steroid 11β-hydroxylating activity, which is associated with the inner mitochondrial membrane, was either partially or completely blocked. The ethidium bromide-treated cells contained mitochondria of varying sizes and with poorly developed inner membranes. The biochemical and morphological effects of ethidium bromide on the cortical cell mitochondria were only partially reversible.
THYROID-STIMULATING AND LIPOLYTIC ACTIVITIES OF PURIFIED PREPARATIONS OF HUMAN THYROID-STIMULATING HORMONE
Authors: HARTREE ANNE STOCKELL , THOMAS MARJORIE , FURNIVAL BRIDGET E. , BURNS T. W. , LANGLEY P. 
Published: December 2008

SUMMARY
A partially purified fraction of human thyroid-stimulating hormone (DEAE-II) was further purified by ion-exchange chromatography on IRC-50, gel-filtration on Sephadex G-100 and finally chromatography on DEAE-cellulose. Two fractions were obtained which were high in thyroid-stimulating activity (8·3 and 7·3 units human Research Standard A/mg) and were comparable in potency to other preparations of the human hormone reported in the literature. They were also electrophoretically heterogeneous as were the preparations of other workers. Lipolytic activity toward cells obtained from human or rat adipose tissue was demonstrated for all fractions containing thyroid-stimulating activity, the two activities being roughly parallel. It is concluded that both thyroid-stimulating and lipolytic activities are probably present in the same protein molecule, but it is unlikely that the latter activity is of physiological significance.
RELATIONSHIP BETWEEN THE THYROID HORMONE AND MINERAL METABOLISM IN THE RAT
Authors: HUMPHRAY H. P. , HEATON F. W. 
Published: December 2008

SUMMARY
The effect of thyroid activity on the distribution of magnesium, potassium and calcium between plasma, soft tissues and bone was investigated in adolescent rats. Administration of thyroxine or propylthiouracil produced variable effects on their concentrations in tissues, but the total amounts of all three metals in the complete liver and a single femur showed consistent changes that were similar to changes in the nitrogen content of the liver and the dry weight of bone. It is concluded that the influence of thyroid hormone on mineral metabolism is secondary to its action on tissue anabolism and catabolism.
Magnesium deficiency decreased thyroid activity, and loading with magnesium salts increased the activity of the gland, a very close relationship being observed between the plasma magnesium concentration and the activity of the thyroid. Deficiency or loading with potassium salts produced changes that were qualitatively similar to those with magnesium, but less well-defined, and it appears that potassium may have an indirect effect on the gland. A hypothesis is advanced to explain how, in the absence of a homeostatic relationship, the availability of magnesium could modulate thyroid activity.
ESTIMATION OF MARSUPIAL RENIN USING MARSUPIAL RENIN-SUBSTRATE
Authors: SIMPSON PAMELA A. , BLAIR-WEST J. R. 
Published: December 2008

SUMMARY
Bilateral nephrectomy of an Eastern Grey kangaroo (Macropus giganteus) increased plasma renin-substrate concentration approximately tenfold when compared with intact kangaroos. A preparation made from this plasma had a renin-substrate concentration of 3000 ng/ml. A pH profile of rate of reaction with pig renin had an optimum at pH 5·39. By comparison, the pH optimum of sheep renin-substrate was pH 6·15. Estimates of plasma renin concentration for kangaroos, wombats and wallabies, using kangaroo renin-substrate or sheep renin-substrate were highly correlated. Results from incubation with sheep renin-substrate were greater and hence indicate the advantage in using this substrate for marsupial renin estimation.
The consistently large difference between sheep and kangaroo renin-substrate when incubated with renin from marsupial and eutherian species appears to be due to a structural difference between the two substrates, probably near the C-terminal end of the angiotensin I molecule.
STANDARDIZATION AND EVALUATION OF A SENSITIVE AND CONVENIENT ASSAY FOR MELANOCYTE-STIMULATING HORMONE USING ANOLIS SKIN IN VITRO
Authors: BJÖRKLUND A. , MEURLING P. , NILSSON G. , NOBIN A. 
Published: December 2008

SUMMARY
A method is described for the quantitative bioassay of melanocytestimulating hormone (MSH) activity using the skin of the lizard Anolis carolinensis in vitro. The colour changes were registered photoelectrically as changes in reflexion of green monochromatic light. Synthetic α-MSH (CIBA-Geigy Ltd) was used as standard. The method can detect MSH activity at a concentration down to 0·01–0·05 ng α-MSH/ml, and allows the detection of MSH activity in normal rat plasma. The mean precision of the assay λ is about 0·13. This assay thus combines high sensitivity with good precision, and is also comparatively rapid, easy to handle and inexpensive.
ACUTE DEPLETION OF THE HORMONAL-IODINE STORES FROM THE THYROID GLAND AFTER BIRTH IN LAMBS
Authors: ŚLEBODZIŃSKI A. 
Published: December 2008

SUMMARY
Hormonal iodine metabolism was studied in newborn lambs born to sheep which had been injected with 131I 3–11 days earlier. A rapid outflow of the pre-formed foetal hormone occurred immediately after birth causing a loss of 41% of the pre-formed hormone within 15 min and a loss of 60% of iodine pre-accumulated in thyroglobulin 5 h later (as revealed by histochemistry). Postnatal hypersecretion was followed by a short-lived rise in serum protein-bound iodine and free thyroxine (measured indirectly).
Assuming that thyrotrophin (TSH) is a major stimulator of the thyroid secretory activity in the newborn lamb, the sequence of events indicates that the enhanced TSH and thyroxine release begins as a result of the stress of parturition rather than as a result of body-cooling thereafter.
EFFECTS OF PINEALECTOMY, CONSTANT LIGHT AND DARKNESS ON GROWTH HORMONE LEVELS IN THE PITUITARY AND PLASMA OF THE RAT
Authors: RELKIN R. 
Published: December 2008

SUMMARY
The effects of constant light, constant darkness, and diurnal lighting, in combination with pinealectomy or sham pinealectomy, on pituitary and plasma concentrations of radio-immunoassayable growth hormone (GH) were investigated in 23- to 24-day-old male rats. In addition, the effects on pituitary, accessory sex organ, testes, adrenal and body weights, as well as tail length, were measured. Three days after operation random groups of pinealectomized and sham-pinealectomized animals were placed in either continuous light, continuous darkness or diurnal light, and killed 28–29 days later. Analysis of the results revealed that the sham-pinealectomized group exposed to constant darkness differed from the other five groups by showing lower pituitary and plasma GH concentrations, body weight, tail length and accessory sex organ weight relative to body weight and testes weight. No statistically significant differences were found in pituitary or adrenal weights. It is concluded that increased pineal function occurring in darkness probably inhibits secretion of GH releasing factor, decreasing pituitary synthesis and release of GH.
STIMULATION BY OVINE PROLACTIN OF FLUID TRANSFER IN EVERTED SACS OF RAT SMALL INTESTINE
Authors: RAMSEY D. H. , BERN H. A. 
Published: December 2008

SUMMARY
Ovine prolactin injected subcutaneously for 2 days stimulated an increase in fluid uptake in vitro by everted gut sacs from male Sprague—Dawley rats. Four intestinal segments from each rat were incubated, but only two of the four segments tested showed a prolactin-stimulated increase in fluid transfer in intact rats. In adrenalectomized—nephrectomized rats all four sacs showed an increased fluid transfer after prolactin treatment. Sacs incubated for 1 h in glucose—Ringer solution containing 0·1 mg ovine prolactin/ml did not show an increased water transfer as compared with controls incubated in medium containing albumin. Dietary changes seemed to alter the sensitivity of the gut to prolactin.
METABOLISM OF PORCINE, HUMAN AND SALMON CALCITONIN IN THE RAT
Authors: de LUISE M. , MARTIN T. J. , GREENBERG P. B. , MICHELANGELI V. 
Published: December 2008

SUMMARY
Whereas the liver is the major site of accumulation of 125I-labelled porcine calcitonin soon after injection in the rat, both human and salmon calcitonin were rapidly taken up in rat kidney, with relatively insignificant amounts found in the liver.
In-vitro studies of degradation of 125I-labelled calcitonins showed that human calcitonin was readily degraded by most rat tissues but the major activity was found in a kidney microsomal fraction, whereas the liver supernatant was most active towards pig calcitonin. Salmon calcitonin was resistant to breakdown by all tissues and fractions except the kidney microsomal fraction, which rapidly degraded it to trichloroacetic acid-soluble fragments. Liver homogenates from a number of mammalian and non-mammalian species degraded pig calcitonin but had little effect on salmon calcitonin.
The results show that the kidney is the most important organ in the metabolism of human and salmon calcitonin in the rat, while confirming that the liver is mainly responsible for the metabolism of porcine calcitonin.
RNA SYNTHESIS IN THE MOUSE OVIDUCT AND UTERUS: VARIATIONS BEFORE, DURING AND AFTER ZYGOTE TRANSPORT
Authors: BRONSON F. H. , HAMILTON T. H. 
Published: December 2008

SUMMARY
Two experiments were performed to examine variations in whole-organ concentrations of RNA, DNA and protein, and specific activities of RNA in vivo in the mouse oviduct and uterus during the oestrous cycle and early pregnancy. Concentrations of DNA did not vary in the oviduct at any stage of the reproductive cycle in either study. In the first experiment with Yale Swiss mice, the concentration of RNA in the oviduct was highest at pro-oestrus, somewhat lower at mid-day of oestrus, and lowest on days 2, 4 and 12 after insemination. Concentrations of RNA were essentially identical in the oviducts of inseminated and non-inseminated females at mid-day of the day following ovulation. The second experiment, using CF-1 mice, confirmed these results, and, in addition, examined oviducal and uterine uptake and incorporation of [3H]uridine. Incorporation of the radioactive precursor into RNA was highest in the oviduct at mid-day of pro-oestrus, was markedly decreased before ovulation, and remained relatively low during the period of egg transport in both inseminated and non-inseminated mice. Most of the RNA necessary for appropriate oviducal function during zygote transport, therefore, is synthesized well before ovulation, and relatively little is formed during the 3 days of tubal residence. The general pattern of incorporation of [3H]uridine into RNA in the uterus appeared basically similar to that shown by the oviduct, except at mid-pregnancy when transcriptional activity of the oviduct genome was relatively low. The two organs also differed markedly in the magnitude of the pro-oestrous surge in RNA synthesis and accumulation, with the uterus showing a greater increase.
THE EFFECT OF AGE, SEX, PREGNANCY, OESTROGEN AND PROGESTOGEN ON RAT SERUM PROTEINS
Authors: HORNE C. H. W. , FERGUSON J. 
Published: December 2008

SUMMARY
Using a radial immunodiffusion technique the levels of four serum proteins, albumin, transferrin, slow α1-globulin and γ2-globulin, were measured in normal rats to determine the effects on these proteins of age, sex, pregnancy and of the administration of oestrogen (mestranol) and progestogen (ethynodiol diacetate). Significant increases in albumin, slow α1-globulin and γ2-globulin were found with increasing age, and highly significant differences in albumin and slow α1-globulin occurred between male and female rats. During pregnancy significant increases in slow α1-globulin and transferrin were found but albumin and γ2-globulin concentrations fell. Oestrogen administration resulted in significant increases in slow α1-globulin and transferrin, but albumin and γ2-globulin were unaltered. In the progestogen-treated group the concentrations of all four proteins were unchanged.
THE EFFECTS OF FOETAL THYROIDECTOMY ON THE DEVELOPMENT OF THE OVINE FOETUS
Authors: HOPKINS P. S. , THORBURN G. D. 
Published: December 2008

SUMMARY
Thyroid glands were surgically ablated from foetal sheep between 81 and 96 days of gestation in order to study the role of the thyroid gland in foetal development. Gestation of ewes bearing thyroidectomized foetuses was prolonged by about 5 days, and athyroid lambs failed to survive more than 24 h. Athyroid foetuses delivered by Caesarian section 1 week before term were characterized by low body weight, low thymus gland weight, and shortened limbs. Foetal thyroidectomy markedly retarded both the maturation and growth of wool follicles and osseous tissue.
Plasma concentrations of growth hormone, calcium and phosphorus were normal in the athyroid foetuses, but cholesterol levels were increased. The absence of thyroxine in the foetal circulation agrees with previous findings that the ovine placenta is impermeable to maternal thyroxine.
THE EFFECT OF OESTROGENS ON THE RESPONSE OF BONE TO PARATHYROID HORMONE IN VITRO
Authors: ATKINS D. , ZANELLI JOAN M. , PEACOCK M. , NORDIN B. E. C. 
Published: December 2008

SUMMARY
An organ culture system was used to examine the effects of oestrogens on the response of 5-day-old mouse calvaria to parathyroid hormone (PTH). Parathyroid hormone released calcium and phosphate from the bone and this was associated with an increase in glucose consumption, an accumulation of citric acid and an inhibition of citrate oxidation. Oestradiol, oestriol, oestrone and ethinyl oestradiol all inhibited the PTH-induced release of calcium. The accumulation of citrate was prevented without the PTH-induced block on citrate oxidation being removed, and this was explained in terms of a reduction in glycolysis. Oestradiol, oestriol and oestrone appeared to be of equal potency. However, ethinyl oestradiol was active at much lower doses but appeared to be toxic at higher levels.
SECRETION OF PROLACTIN AND LUTEINIZING HORMONE AT OESTRUS IN THE EWE
Authors: CUMMING I. A. , BROWN JOAN M. , GODING J. R. , BRYANT GILLIAN D. , GREENWOOD F. C. 
Published: December 2008

SUMMARY
Studies of the effect of mating on the release of prolactin over a 47-h period from the onset of oestrus in the ewe are presented. Surges of prolactin occurred around the time of pre-ovulatory luteinizing hormone release, and in some instances copulation appeared to result in an additional surge of prolactin secretion.