bluuebunny/crossref_metadata_2025_split huggingface dataset:
THE RELATIONSHIP BETWEEN THE UTERUS AND OVARIES DURING EARLY PREGNANCY IN THE GUINEA-PIG
Authors: BLATCHLEY F. R. , DONOVAN B. T. 
Published: December 2008

SUMMARY
In mated guinea-pigs one uterine horn was rendered sterile by ligation of the oviduct 2 or 3 days after finding spermatozoa in the vaginal smear. Two glass beads were inserted into the sterile horn on each of days 3–12 and on day 14 in experimental animals but not in controls. At autopsy on day 20 large corpora lutea were present in both ovaries of the control animals. The presence of beads that had been introduced on days 3 and 4 and on days 10–14 resulted in marked regression of the corpora lutea in the adjacent ovary, in the absence of a decidual reaction in the uterus, while luteal enlargement typical of pregnancy occurred in the contralateral ovary. Beads inserted on days 5–8 caused decidualization in the sterile horn but did not induce premature luteal regression in the ipsilateral ovary.
THE EFFECT OF PROLACTIN AND GROWTH HORMONE ON FATTY ACID SYNTHESIS BY PREGNANT MOUSE MAMMARY GLAND IN ORGAN CULTURE
Authors: WANG D. Y. , HALLOWES R. C. , BEALING J. , STRONG C. R. , DILS R. 
Published: December 2008

SUMMARY
The effect of various hormones on the incorporation of [14C]acetate into the fatty acids of pregnant mouse mammary gland explants in organ culture was studied.
Of the hormones insulin (I), ovine prolactin (P), bovine growth hormone (GH) and cortisol (F) tested singly, only insulin stimulated fatty acid synthesis. There was synergism between cortisol or prolactin with insulin. The greatest stimulation in fatty acid synthesis occurred when explants were incubated in a medium containing either I + F + P or I + F + GH.
Analysis by radio-gas-liquid chromatography of the fatty acids synthesized by explants after 14C labelling, showed that the pattern of fatty acids formed in the presence of I + F was distinctly different from that produced in the presence of I + F + P or I + F + GH. In the presence of I + F, the pattern of fatty acids resembled that found in mouse adipose tissue, whilst with I + F + P or I + F + GH the pattern resembled that of mouse milk fat.
Synthesis of RNA was essential for the stimulation of fatty acid synthesis in explants incubated in medium containing I + F + P or I + F + GH. Results obtained when DNA synthesis was blocked with mitomycin C suggest that mitosis is important for the induction of milk-fatty acid synthesis.
Puromycin had no effect for up to 8 h on explants which had been previously cultured in medium containing I + F, I + F + P or I + F + GH. This suggests a slow turnover rate of the enzymes involved in the synthesis of milk fatty acids.
THE SITES OF IODIDE CONCENTRATION IN THE OVIDUCT AND THE UTERUS OF THE RAT
Authors: BROWN-GRANT K. , ROGERS A. W. 
Published: December 2008

SUMMARY
Previous studies have shown that under the influence of progesterone the concentrations of radioiodide in the uterus and oviduct of the rat are maintained at levels higher than that in the plasma. In the present experiments the uterus and oviducts from rats killed 2 h after the injection of Na125I were autoradiographed by a technique which permits the localization of diffusible radioactive material. In intact non-pregnant rats and ovariectomized rats not injected with progesterone, uniformly low grain densities were observed over sections of oviduct and uterus with the exception of the epithelium and lumen of the oviduct where some increase in grain density was observed. In intact and ovariectomized rats treated with progesterone and in rats killed on Day 3 or 4 of pregnancy, grain densities over the epithelium and lumen of the oviduct were very high but the fimbria of the oviduct were consistently unlabelled. The stroma underlying the oviduct epithelium was also labelled. In the uteri of these animals the principal site of concentration of radioiodide was the luminal epithelium, but for technical reasons it was not possible to exclude the stroma immediately adjacent to the luminal epithelium as a less active site of concentration of iodide. No other site in the uterus concentrated radioiodide. The luminal epithelium occupies less than 3% of the volume of the uterus in ovariectomized rats: if this tissue is taken as the sole site of iodide concentration in the uterus, the levels reached in these cells must be at least a hundred times that of the plasma when the overall uterus: plasma concentration ratio for radioiodide is 4 or more.
CORTICOTROPHIN RELEASE INDUCED BY SURGICAL TRAUMA AFTER TRANSECTION OF VARIOUS AFFERENT NERVOUS PATHWAYS TO THE HYPOTHALAMUS
Authors: MAKARA G. B. , STARK E. , MARTON J. , MÉSZÁROS T. 
Published: December 2008

SUMMARY
Corticotrophin (ACTH) release induced by surgical trauma under pentobarbitone anaesthesia was studied in rats. The plasma corticosterone level was used as an index of 'rapid' ACTH release.
One hour after surgical trauma the plasma corticosterone level had risen in rats with various cuts around the medial basal hypothalamus except in the group with lateral cuts. After stress no significant difference was found between the plasma levels of the controls and those of the rats with anterior, 'low' superior, 'low' anterosuperior, and 'short' posterior cuts. In contrast, in rats with 'high' superior, 'high' anterosuperior, 'long' posterior and lateral cuts the plasma corticosterone level was lower than in the appropriate sham-operated controls.
It is suggested that the nerve fibres initiating ACTH release after surgical trauma ascend the spinal cord to the medulla and mid-brain whence the pathways pass forward in the region of the dorsal longitudinal fasciculus and/or the median forebrain bundle to the lateral hypothalamic area, and from there to the medial basal hypothalamus.
PROGESTERONE CONCENTRATION IN THE PERIPHERAL PLASMA OF PREGNANT GOATS
Authors: IRVING G. , JONES D. E. , KNIFTON A. 
Published: December 2008

SUMMARY
Plasma progesterone concentration was measured by a competitive protein-binding method in serial samples of jugular venous blood from 21 pregnant goats, 11 with twin and 10 with single foetuses.
Progesterone levels in twin pregnancies were significantly greater than in singletons. The mean progesterone concentration (ng/ml plasma) in the twin pregnancies was greatest during the 3rd month of gestation (10·7 ± 0·4 (s.e.m.)) and in the singletons during the 4th month (7·8 ± 0·2 (s.e.m.)). There was a significant decrease in mean progesterone concentration in the last month of pregnancy due to a steady decline in the last 7 days before parturition.
The mean progesterone concentrations at parturition in five twin and eight single pregnancies were 2·2 ± 0·4 and 1·5 ± 0·2 (s.e.m.) ng/ml plasma respectively; there was no significant difference between these values. In cord blood from nine kids immediately after delivery the progesterone concentration was 0·9 ± 0·1 ng/ml.
THE EFFECT OF PROSTAGLANDIN F2α AND PROSTAGLANDIN E2 UPON LUTEAL FUNCTION AND OVULATION IN THE GUINEA-PIG
Authors: BLATCHLEY F. R. , DONOVAN B. T. 
Published: December 2008

SUMMARY
The effect of treatment with prostaglandin F2α (PGF2α on luteal function was examined in hysterectomized guinea-pigs. Regression of corpora lutea was found to occur when 0·25 mg (or more) was injected daily for 3 days and ovulation usually ensued within 5 days after treatment. The administration of 1 mg PGF2α daily for 7 days caused marked luteolysis but ovulation did not occur. Ovulation was blocked in three of four intact female guinea-pigs given 1 mg PGF2α/day for 7 days from day 15, but took place normally in five females injected with 0·25 mg/day. Treatment of hysterectomized guinea-pigs with 0·62 mg adrenaline hydrochloride/day, 1·97 mg atropine sulphate/day or 0·52 mg histamine dihydrochloride/day did not cause luteal regression, while the injection of 0·25 mg or 1 mg prostaglandin E2 daily for 3 days was likewise ineffective.
DIFFERENTIAL EFFECTS OF CASTRATION AND DENERVATION ON PROTEIN SYNTHESIS IN THE LEVATOR ANI MUSCLE OF THE RAT
Authors: BUREŠOVÁ M. , GUTMANN E. , HANZLÍKOVÁ V. 
Published: December 2008

SUMMARY
The effects of testosterone on weight changes, incorporation of labelled precursors into RNA and proteins, and on ultrastructure of the levator ani muscle of male rats in which castration or denervation was performed, were studied.
No increase of weight occurred in the denervated levator ani muscle after castration. There was no increase in the incorporation of labelled precursors into RNA and proteins in vitro in mature rats, if the muscle was denervated. However, incorporation still increased when denervation was performed in sexually immature animals. The levator ani muscle, which normally undergoes postnatal involution in the female rat, could be maintained even after postnatal denervation if testosterone was administered at birth, the hormone acting as a nerve-independent trophic agent.
The increase of protein synthesis in the levator ani of mature, male, castrated animals, induced by testosterone administration, was abolished after denervation of the muscle. The activating influence of testosterone upon protein synthesis was, however, still present in immature male animals.
LUTEAL MAINTENANCE IN THE HYPOPHYSECTOMIZED PSEUDOPREGNANT RABBIT: EFFECT OF OVINE LUTEINIZING HORMONE AND FOLLICLE-STIMULATING HORMONE
Authors: DAVIES J. , HOFFMAN L. H. , DAVENPORT G. R. 
Published: December 2008

SUMMARY
Ovine luteinizing hormone (LH) (300 μg/day in divided subcutaneous doses) had a luteotrophic effect of limited duration in intact and hypophysectomized 10-day pseudopregnant rabbits (6–10 days in intact animals; 3–6 days in hypophysectomized animals). Higher dose levels caused reovulation in which case luteolysis occurred. Suppression of reovulation with anti-ovine follicle-stimulating hormone (FSH) serum permitted the daily dose of LH to be raised to 750 μg without causing luteolysis or reovulation. Anti-LH serum was luteolytic in the intact animals. A combination of ovine FSH (200 μg) and LH (300 μg) was indistinguishable from LH alone in terms of its luteotrophic effect in hypophysectomized 10-day pseudopregnant rabbits. Ovine FSH at large daily dose levels (1000 μg) was more effectively luteotrophic than LH alone in a significant number of animals for 10 days after hypophysectomy: endometrial changes in these animals resembled those only seen in normal pregnancy. The luteotrophic effect of 1000 μg FSH was believed to be dependent on a small but significant content of LH, estimated to be about 10 μg. Ovine FSH and anti-FSH serum in intact pseudopregnant rabbits had no detectable effect on luteal function. Animals hypophysectomized at the 7th day and treated with 300 or 500 μg LH/day showed no luteal maintenance for 6 days nor was reovulation induced. Sensitivity to the luteotrophic effect of LH was deemed, therefore, to be greater at 10 than at 7 days of pseudopregnancy. Endometrial criteria were found to be reliable indicators of luteal function. The appearance of ciliated cells was correlated with the decline of the corpora lutea. When reovulation occurred, a new progestational cycle was rapidly superimposed on the existing one.
EFFECTS OF PROGESTERONE, MEDROXYPROGESTERONE ACETATE (PROVERA) AND OESTRONE ON SHEDDING AND DISSOLUTION OF THE ZONA PELLUCIDA IN THE RAT
Authors: DICKMANN Z. 
Published: December 2008

SUMMARY
The effects of progesterone, medroxyprogesterone acetate (MPA), and oestrone on shedding and dissolution of the zona pellucida were studied in intact pregnant rats, ovariectomized pregnant, and ovariectomized pseudopregnant rats into whose uteri blastocysts had been transferred. Treatment with progesterone, MPA and oestrone delayed shedding of the zona. The highest percentage of blastocysts delaying, and with the longest delay period, occurred in ovariectomized, progesterone-treated rats. Ovariectomy of pregnant rats, and treatment of ovariectomized rats with progesterone, MPA or oestrone, delayed dissolution of the zona. Oestrone together with progesterone caused both shedding and dissolution of the zona within 24 h. It is deduced that in the intact pregnant rat, the synergistic action of oestrogen superimposed on progesterone synchronizes shedding and dissolution of the zona so that they occur together at a specified time.
CALCITONIN CLEARANCE IN THE PIG AND IN THE ISOLATED PERFUSED PIG LIVER
Authors: GREENBERG P. B. , MARTIN T. J. , MELICK R. A. , JABLONSKI P. , WATTS J. McK. 
Published: December 2008

SUMMARY
The metabolic clearance rate (MCR) of porcine calcitonin in six gilts was 13·0 ± 0·7 (s.e.m.) ml/min/kg and in four isolated, perfused pig livers was 16·1 ± 1·1 ml/min, with constant infusions of porcine calcitonin and measurement of calcitonin concentration by radioimmunoassay.
After single injections of 125I-labelled porcine calcitonin, the MCR of 125I-labelled porcine calcitonin was 29·2 ± 2·8 ml/min in six isolated, perfused pig livers.
125I-labelled salmon calcitonin was cleared at a slower rate than porcine calcitonin after single injections into the gilt. 125I-Labelled human calcitonin and 125I-labelled salmon calcitonin were not significantly cleared by the isolated, perfused pig liver.
EFFECT OF VARIOUS ADRENERGIC RECEPTOR STIMULATING AND BLOCKING AGENTS ON HUMAN GROWTH HORMONE SECRETION
Authors: MASSARA F. , CAMANNI F. 
Published: December 2008

SUMMARY
The effects of various adrenergic substances, either alone or in association with alpha and beta blocking agents, on human plasma growth hormone (GH) were studied in 36 normal volunteers.
Plasma GH levels were unaffected by i.v. adrenaline (10 μg/min for 30 min) or by propranolol (1·5 mg/min for 10 min). Given together at the same doses, these drugs provoked sharp increases in plasma GH (from 8·5 to > 100 ng/ml; a mean increase of 30±8·02 (s.e.m.)). Reduction of the adrenaline dose to 7 μg/min produced a positive response in four out of six cases.
The GH response to propranolol plus adrenaline was suppressed by simultaneous administration of phentolamine, but not significantly altered by glucose and aminophylline. Noradrenaline (7–14 μg/min for 30 min) produced no changes in plasma GH levels in six cases, while its association with propranolol was followed by an increase in only one out of four cases. Phenylephrine and tyramine were without effect, with or without propranolol.
In five out of six cases, GH values gradually increased after oral administration of 1 g l-DOPA (from 4·2 to 85 ng/ml; mean, 30·2). This response was totally suppressed by phentolamine.
It is considered that stimulation of GH by propranolol plus adrenaline and l-DOPA is mediated by alpha-adrenergic receptors. The possible role of a beta-inhibiting effect is discussed.
ACTION OF OESTRADIOL-17β AND CYCLIC AMP ON THE SYNTHESIS OF RNA, PHOSPHOPROTEINS AND PHOSPHOLIPIDS IN THE UTERUS OF OVARIECTOMIZED RATS IN VITRO
Authors: RAO K. N. , TALWAR G. P. 
Published: December 2008

SUMMARY
Administration of oestradiol-17β to ovariectomized rats increases the incorporation of [32P]orthophosphate into RNA, phosphoproteins and phospholipids of the uterus. Uteri taken from the ovariectomized rats pretreated with oestradiol for 1 h in vivo continued to manifest enhanced ability to incorporate 32P into RNA, phospholipids and phosphoproteins when tested in vitro. However, when oestradiol was added directly to the incubation medium, it failed to stimulate to the same extent the incorporation of [32P]orthophosphate into RNA and phosphoproteins in excised uteri from ovariectomized rats. An increase in the incorporation of 32P into phospholipids was obtained only after prolonged incubation of the excised uteri in the medium containing oestradiol.
A number of experimental approaches has been tried to reproduce more completely the in-vivo actions of oestradiol on the rat uterus in vitro. Supplementation of the medium with hormones such as insulin, progesterone and biogenic amines like adrenaline, histamine and serotonin besides oestradiol was not sufficient to attain the metabolic capacities of the uterus from animals primed with oestradiol in vivo. Oestrone was not effective. The presence of tissues such as liver, parametrial fat, adrenal glands or anterior pituitary in the incubation medium did not modify the lack of full response of ovariectomized rat uteri to oestradiol in vitro.
Studies were also extended to uteri incubated in the peritoneal cavity of ovariectomized rats instead of in synthetic media. Moreover the uteri of rats in pro-oestrus and dioestrus were also tested in vitro for their lack of full invivo-like response to oestradiol.
Cyclic 3′,5′-AMP and AMP stimulated in vitro the incorporation of [32P]orthophosphate into RNA but not into phosphoproteins and phospholipids.
Results are discussed and arguments made for the lesion possibly preventing the full development of the uterotropic action of the hormone in vitro, even though limited effects of the hormone were obtained.
LUTEINIZING HORMONE RELEASING FACTOR IN ULTRAFILTRATES OF BLOOD COLLECTED FROM THE PITUITARY STALK OF OVARIECTOMIZED RATS AND RATS SUBJECTED TO ELECTRICAL STIMULATION OF THE PREOPTIC AREA
Authors: BURGER H. G. , FINK G. , LEE V. W. K. 
Published: December 2008

SUMMARY
The presence of luteinizing hormone releasing factor (LH-RF) activity was investigated in pituitary stalk and systemic blood collected from rats ovariectomized at least 3 weeks previously, and in stalk blood from male rats in which electrodes had been implanted in the medial preoptic area of the brain. Most of the assayable luteinizing hormone (LH) present in the blood samples was eliminated by acid-ethanol extraction followed by ultrafiltration. The ultrafiltrates were injected into ovariectomized rats treated with oestrogen and progesterone, and increments in the concentration of LH in the sera of these animals, estimated by radioimmunoassay, were taken as an indication that the filtrate was able to release LH from the anterior pituitary gland. The ultrafiltrates of both the stalk and systemic plasma from the ovariectomized rats exhibited LH-RF activity as did the ultrafiltrates of blood collected from the pituitary stalk of the male rats during electrical stimulation of the preoptic area; stalk blood collected from these animals before the current was applied appeared to be inactive. The LH-RF activity of the ultrafiltrates of systemic and pituitary stalk plasma taken from ovariectomized rats was similar, and, therefore, the possibility is raised that the response of the pituitary glands in ovariectomized rats treated with oestrogen and progesterone is of an all or none type. The presence of appreciable quantities of LH-RF in the systemic plasma of ovariectomized rats may explain the discrepancy between bioassay and immunoassay estimates of LH in the plasma of these animals. The rapid increase in the concentration of serum LH and in the LH-RF activity of pituitary stalk plasma which followed stimulation of the preoptic area suggests that this region of the brain may be important in the control of the secretion of LH in the male as well as in the female animal.
THE ROLE OF THE STEROID-SENSITIVE CATION-DEPENDENT ATPASE IN HUMAN PROSTATIC TISSUE
Authors: FARNSWORTH W. E. 
Published: December 2008

SUMMARY
The purposes of this study were: (1) to determine if a (Na+ + K+)-dependent, ouabain-sensitive, androgen-responsive ATPase is present in the microsomal fraction of the human prostate as it is in the rat ventral prostate; (2) to determine the degree and nature of interaction and interdependence of the ATPase with the steroid-binding and steroid-metabolizing activities of the prostate and, also, with the histological characteristics of the gland. The results indicate that ATPase which shows particular responsiveness to 5α-dihydrotestosterone, 5α-androstane-3α,17β-diol and dehydroepiandrosterone is present. The microsomes, which contain this enzymic activity, show relatively high affinity for the active steroids and for oestradiol-17β. The intrinsic steroid-sensitive, cation-dependent ATPase activity varies widely from gland to gland in parallel with the steroid binding and 3α-hydroxysteroid dehydrogenase activity. In comparisons of the enzymatic complements of glands with different histological features, the concentration of 4-en-3-oxosteroid-5α-reductase activity in tissue showing predominantly epithelial hyperplasia was greater than that in normal or carcinomatous glands or glands with stromal hypertrophy. The possible role of the ATPase as a mediator of hormonal stimulation, and the implications of the findings to an understanding of the development of benign prostatic hypertrophy, are discussed.
BLOOD LEVELS OF OXYTOCIN IN THE FEMALE GOAT DURING COITUS AND IN RESPONSE TO STIMULI ASSOCIATED WITH MATING
Authors: McNEILLY A. S. , DUCKER H. ALISON 
Published: December 2008

SUMMARY
Blood oxytocin was assayed on the lactating guinea-pig mammary gland. Thirty-six series of serial jugular blood samples were collected from 33 oestrous female goats during normal mating and the transient appearance of oxytocin (2 to 190 μu./ml plasma) was detected in 28 of the series. Coitus did not appear to be a major stimulus for the release of oxytocin. However, oxytocin release occurred in many experiments shortly before coitus when the male was present and continued after coitus for varying times up to 16 min after the male had left the mating room. Oxytocin (9–150 μu./ml plasma) was also released during simulated mating in all six experiments carried out in six dioestrous female goats.
In a further 16 oestrous female goats, oxytocin release (7–73 μu./ml plasma) occurred in response to individual exteroceptive stimuli associated with mating and these stimuli could be classified in descending order of effectiveness in causing oxytocin release as follows: presence of another goat > smell of the male > sound of the male > sight of the male.
The results indicate that oxytocin release occurs in oestrous female goats in response to a complex of stimuli occurring during mating and that physical stimuli associated with coitus are only important in causing oxytocin release during simulated mating in dioestrous female goats.
VARIATIONS IN THE BLOOD VOLUME OF THE NEURAL AND ANTERIOR LOBES OF THE PITUITARY OF THE RAT ASSOCIATED WITH NEUROHYPOPHYSIAL HORMONE-RELEASING STIMULI
Authors: SOORIYAMOORTHY T. , LIVINGSTON A. 
Published: December 2008

SUMMARY
Measurements of the blood volume of the neural and anterior lobes of the pituitaries of rats using 51Cr-labelled erythrocytes indicated that all stimuli examined which released neurohypophysial hormones also led to a significant increase in neural lobe blood volume. The blood volume of the anterior lobe was not altered by any of these stimuli.
Experiments with parasympathetic blocking drugs indicated that this mechanism involved cholinergic pathways, a conclusion which was supported by the results of experiments with parasympathomimetic drugs. Sympathetic blockers and sympathomimetic drugs produced no appreciable effects on the blood volume responses.
It is concluded that vasodilation occurs in the neural lobe of the rat associated with stimuli which are known to release neurohypophysial hormones and that this vasodilation involves cholinergic mechanisms but that these pathways may not be identical with those responsible for hormone release.