bluuebunny/crossref_metadata_2025_split huggingface dataset:
3α-HYDROXYSTEROID DEHYDROGENATION IN SUBCELLULAR FRACTIONS OF RAT VENTRAL PROSTATE AND OTHER TISSUES
Authors: GORE MARION B. R. , BARON D. N. 
Published: December 2008

SUMMARY
Dehydrogenation of androsterone, catalysed by both particulate and soluble fractions of rat ventral prostate, has been demonstrated in vitro by spectrophotometric and chromatographic methods. A difference has been observed between dehydrogenases in the particulate and soluble fractions in their acceptance, under uniform experimental conditions, of the 5α and 5β isomers, androsterone and aetiocholanolone, as substrate. The particulate enzyme dehydrogenates androsterone under conditions in which aetiocholanolone is not dehydrogenated, whereas the soluble enzyme utilizes equally androsterone and aetiocholanolone as substrate. An examination of other rat tissues by the chromatographic method has confirmed the widespread occurrence of the soluble dehydrogenase. Particulate dehydrogenase resembling the prostatic enzyme was detected in seminal vesicle and kidney.
THE INFLUENCE OF VARIOUS HORMONES ON THE RETICULO-ENDOTHELIAL SYSTEM: ENDOCRINE CONTROL OF BODY DEFENCE
Authors: NICOL T. , VERNON-ROBERTS B. , QUANTOCK D. C. 
Published: December 2008

SUMMARY
(1) The three principal natural oestrogens, oestrone, oestriol and 17β-oestradiol, are strong stimulants of the reticulo-endothelial system (RES).
(2) Testosterone had no effect on the RES when administered alone. Doses of testosterone which inhibited the oestrogenic response of the reproductive tract to oestrone and oestriol also inhibited the stimulant effect of these oestrogens on the RES. In contrast, testosterone markedly potentiated the stimulant effect of 17β-oestradiol on the RES even in doses at which the oestrogenic response is inhibited. These results imply that 17β-oestradiol is the principal oestrogen concerned in the control of RES activity, and provide further proof that the oestrogen molecule has two biological activities, one acting on the RES and the other on the reproductive tract, and that they act independently although contained in the same molecule.
(3) Progesterone is a mild RE stimulant. Doses which inhibited the oestrogenic response of the reproductive tract did not affect oestrogen-produced RE stimulation.
(4) Small doses of cortisone stimulated the RES, but high doses depressed RE activity and oestrogen-produced RE stimulation.
(5) Thyroxine had no effect on the RES when acting alone, but markedly potentiates oestrogen-produced RE stimulation.
(6) The hormones of the anterior lobe of the pituitary are all stimulants of the RES; and, with the exception of growth hormone and follicle stimulating hormone, acted in a synergistic manner with oestrogen.
(7) The hormones of the posterior lobe of the pituitary had no effect on the RES.
(8) The results as a whole indicate that the endocrine system exerts a homeostatic influence on RE function, and that 17β-oestradiol is the principal stimulant of the RES and body defence.
A STUDY OF THE EFFECT OF RESERPINE ON THYROID SECRETION IN SEVERAL MAMMALIAN SPECIES
Authors: PREMACHANDRA B. N. 
Published: December 2008

SUMMARY
Investigations were carried out to study the effect of reserpine in doses up to 100 μg./100 g. body weight on thyroid function as determined by thyroxine secretion rates (TSR) in the rat, hamster, guinea-pig and mouse. It was found that 20 μg. reserpine/100 g. body weight had no effect on TSR or on body weight. At higher doses (50–100 μg./100 g.) TSR was depressed, greater depression being noted with doses of 100 μg. Food intake was reduced at the higher dosage resulting in significant losses of body weight (up to 33%). In long-term studies in rats, administration of 10 μg. reserpine/100 g. body weight for 6 weeks had no effect on TSR. No dose of reserpine that would inhibit TSR without contributing to body weight loss and depression in food intake was found. Administration of reserpine in these low doses did not influence body temperature. Uniform results were obtained in all the species studied. It is concluded that reserpine, in low doses, has no influence on thyroid function as determined by the rate of thyroxine secretion. Higher doses of reserpine, however, inhibit thyroid secretion, but such an inhibition appears to be secondary to the effects of inanition brought about by a toxic action of the drug and/or its hypothalamic effects.
THE SPECIFIC ACTIVITY OF PLASMA CORTISOL IN SHEEP AFTER RAPID INTRAVENOUS INJECTION OF [1,2-3H2]CORTISOL, AND ITS RELATION TO THE RATE OF CORTISOL SECRETION
Authors: HARRISON F. A. , PATERSON J. Y. F. 
Published: December 2008

SUMMARY
Tritium-labelled cortisol was injected intravenously, as a single dose, in 12 experiments on seven sheep with autotransplanted left adrenal glands, in which cortisol secretion rate could be measured directly by sampling adrenal venous blood.
In all experiments, curves which represented sums of two exponential terms could be fitted to the estimates of specific activity of plasma cortisol. The interpretation of the data was based on the distribution of cortisol in two miscible pools, and the calculated rates of cortisol turnover were much greater than the cortisol secretion rates which were measured directly and simultaneously.
Simultaneous injection of Evans blue suggested that 1–2 min. was needed for complete mixing of the injected dose in plasma, during which time labelled cortisol leaves plasma with a half-time of about 1 min. It is concluded that such conditions do not provide a satisfactory basis for tracer kinetic analysis.
FACTORS WHICH INFLUENCE ASSAYS OF GONADOTROPHIN BASED ON THE INDUCTION OF OVULATION IN MICE
Authors: BROWN P. S. , WELLS M. 
Published: December 2008

SUMMARY
The response to gonadotrophins in an assay based on the induction of ovulation in immature mice was reduced by treatment of the experimental animals with barbitone. The responses to follicle-stimulating hormone and luteinizing hormone (LH) were reduced to a similar degree. Lack of specificity of the assay for LH is probably not due simply to the endogenous secretion of this hormone.
Progesterone and oestradiol-17β had no definite effect on the assay but norethynodrel significantly reduced the slope of the dose-response line. Feeding the mice with methylthiouracil increased the sensitivity to a small but significant extent.
Assays depending on the induction of ovulation in immature, pregnant and mature dioestrous mice were compared. Mice of the first two types gave more sensitive and precise assays of human urinary gonadotrophin.
AROMATIZATION OF 7α-HYDROXYDEHYDROEPIANDROSTERONE AND OF ITS 3-SULPHATE BY OVARIAN AND PLACENTAL TISSUE CULTURES
Authors: STÁRKA L. , JANATA J. , NOVÁK J. 
Published: December 2008

SUMMARY
Incubation of 7α-hydroxydehydroepiandrosterone or its sulphate with cultures of ovarian or placental tissue yielded 7α-hydroxyoestrone, 7α-hydroxyoestradiol and a product tentatively characterized as 7-oxo-oestradiol. These results show that the ovary can be the source of 7-oxygenated oestrogens.
EFFECTS OF X-IRRADIATION ON THE ADRENAL GLANDS OF IMMATURE RATS
Authors: WALL P. G. 
Published: December 2008

SUMMARY
Localized X-irradiation of the adrenal glands of male rats aged 3–36 days inhibited subsequent gain in body weight and in the growth of the adrenal glands, the degree of retardation depending on the dose applied (400–1800 r.). The cortico-medullary ratio was essentially the same in irradiated and control animals.
As judged by compensatory hypertrophy of one adrenal gland after the removal of the other, adrenal function was unaffected by X-irradiation within the range of doses and ages investigated.
METABOLIC AND ENDOCRINE EFFECTS OF LYSERGIC ACID DIETHYLAMIDE (LSD-25) ON MALE RATS
Authors: WELTMAN A. S. , SACKLER A. M. 
Published: December 2008

SUMMARY
Male Wistar rats were injected s.c. with 500 or 750 μg./kg. of lysergic acid diethylamide (LSD-25) on alternate days for 2 weeks and received a total of eight injections, the last two being on consecutive days. Before autopsy, urinary 17-ketosteroid output, white blood cell counts, body weight, food and oxygen consumption were studied. Depending on time and dosage, the various results indicate that LSD-25 stimulates adrenal function, lowers metabolism, and inhibits thyroid and possibly gonadal function. Similarities between the effects of LSD-25 intoxication and schizophrenia are noted.
BIOGENESIS OF CORTICOSTEROIDS IN THE EUROPEAN EEL ANGUILLA ANGUILLA L.
Authors: SANDOR T. , VINSON G. P. , JONES I. CHESTER , HENDERSON I. W. , WHITEHOUSE B. J. 
Published: December 2008

SUMMARY
Incubation, with [4-14C]progesterone, of adrenocortical tissue (posterior cardinal vein preparations) from the eel yielded 14C-labelled cortisol and cortisone. These two hormones, containing both 14C and 3H, appeared when similar preparations were incubated simultaneously with [4-14C]progesterone and [16-3H]pregnenolone. In addition, the following intermediaries were isolated: [14C, 3H]progesterone; [14C, 3H]17α-hydroxyprogesterone; [3H]17α-hydroxypregnenolone and [14C, 3H]21-deoxycortisol. Analysis of the isotope content of the end products and isolated intermediaries seemed to indicate that the transformation of pregnenolone to corticosteroids proceeded to a large extent through intermediaries other than progesterone. In none of these experiments could the formation of aldosterone be demonstrated. Similarly, incubation of eel adrenocortical tissue with a mixture of [4-14C]-progesterone and [1,2-3H]corticosterone failed to yield detectable aldosterone.
A further search for aldosterone, using a large amount of eel adrenocortical tissue with [4-14C]progesterone and [16-3H]pregnenolone as substrates with added angiotensin, also gave negative results. In similar preparations, [1-14C]sodium acetate was not transformed to any recognizable corticosteroids.
THE EFFECTS OF ANDROGENIZATION IN MALE RATS CASTRATED AT BIRTH
Authors: MORRISON R. L. , JOHNSON D. C. 
Published: December 2008

SUMMARY
Male rats were castrated on the day of birth and 5 days later half were given 2·5 mg. testosterone propionate (TP) subcutaneously (androgenization). When 30 days old, single animals were treated with graded doses of TP for 10 days. At the same time 57 males were united in parabiosis with normal intact males, and treated for 10 days with androgen.
Androgenization resulted in increased sensitivity of the accessory sex organs to subsequent treatment with TP. Also, the excessive secretion of gonadotrophin by the castrated animals, as measured by androgen production in intact parabiotic partners, was more effectively inhibited by TP in androgenized than in non-androgenized males. The results are consistent with the interpretation that early androgen treatment sensitizes both the male target organs and the hypothalamo-hypophysial system to androgen.
THE DIURNAL PATTERN OF PLASMA GROWTH HORMONE CONCENTRATION IN ADULTS
Authors: HUNTER W. M. , FRIEND J. A. R. , STRONG J. A. 
Published: December 2008

SUMMARY
Plasma growth hormone (GH) levels were measured at intervals throughout the day in various subjects. Several healthy men showed increased levels 3–4 hr. after a meal. Plasma GH was generally low in obese subjects with or without diabetes. Four acromegalic patients had consistently and markedly raised levels which were unaffected by food. In two thyrotoxic patients GH values were not different from normal.
HISTOCHEMICAL DISTRIBUTION OF 3β-HYDROXYSTEROID DEHYDROGENASE AND 17α- AND 17β-HYDROXYSTEROID DEHYDROGENASES IN THE PLACENTA AND FOETAL MEMBRANES OF THE RAT
Authors: BOTTE V. , MATERAZZI G. , CHIEFFI G. 
Published: December 2008

SUMMARY
The placenta and the foetal membranes of rats (pregnant 5–21 days) have been assayed by histochemical methods for 3β-hydroxysteroid dehydrogenase (3β-HSDH), NAD-dependent, and 17α- and 17β-hydroxysteroid dehydrogenases (17α- and 17β-HSDH), both NAD and NADP-dependent.
3β-HSDH was limited to the trophoblastic giant cells of the first generation, whereas 17α- and 17β-HSDH were present in both the first- and second-generation giant cells and also in the endodermal cells of the inverted yolk sac placenta.
MILK-EJECTION ACTIVITY (OXYTOCIN) IN THE EXTERNAL JUGULAR VEIN BLOOD OF THE COW, GOAT AND SOW, IN RELATION TO THE STIMULUS OF MILKING OR SUCKLING
Authors: FOLLEY S. J. , KNAGGS G. S. 
Published: December 2008

SUMMARY
Milk-ejection activity (oxytocin) was assayed in the external jugular vein blood of cows, goats and sows during milking or suckling. 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.
Serial blood samples were taken during machine milking of cows which had been accustomed to the milking routine and blood sampling procedure. The stimulus most consistently followed by a transient appearance of oxytocin in the jugular vein blood was the application of the teat cups. In some cases, there was a second release of oxytocin, later in the milking process, unrelated to any apparent stimulus. There was no evidence in these experiments of any conditioning of oxytocin release to visual, auditory or olfactory stimuli associated with the milking routine.
Serial blood samples were taken during hand-milking of goats which had been accustomed to the milking routine and blood sampling procedure. Oxytocin was detected in jugular vein blood in only a minority of experimental milkings. Irrespective of whether oxytocin was found in the jugular blood the milk yield at the experimental milking did not differ appreciably from the value to be expected from comparable milkings for the preceding week.
Serial blood samples were obtained from sows during suckling, the animals having been accustomed to the presence of the experimenter and the blood sampling procedure. In most of the experimental sucklings oxytocin was found in the blood. The occurrence of the hormone was transient and it was usually released just before the milk-ejection phase. In most of the cases in which no hormone was detected in the blood the piglets obtained no milk as judged by their behaviour.
The results suggest that in the cow and sow the milk-ejection reflex is a neurohormonal reflex involving the release of oxytocin. On the other hand, in the goat, provided the animals are carefully hand-milked, normal milk yields can be obtained without the release of oxytocin.
INFLUENCE OF OESTRADIOL ON CITRATE ACCUMULATION IN THE UTERUS AND BLOOD OF FLUOROACETATE-TREATED RATS
Authors: ECKSTEIN B. , SHALEM M. 
Published: December 2008

SUMMARY
The uterus, ovary and kidney of rats treated with fluoroacetate accumulated large quantities of citrate. It was inferred that a citric acid cycle operates in the uterus, ovary and kidney of castrated and normal rats. After the administration of oestrogen, citrate accumulation 3 hr. after fluoroacetate was slightly increased at 24 hr., but much reduced 96 hr. after the oestrogen had been injected.
It is postulated that during the first 24 hr. after oestrogen injection, oxidative respiration by way of the citric acid cycle takes place. Thereafter alternative metabolic pathways may predominate, the citric acid cycle in the uterus being depressed.
PROGESTERONE AND PLACENTAL DEVELOPMENT IN THE SHEEP
Authors: ALEXANDER G. , WILLIAMS D. 
Published: December 2008

SUMMARY
Pregnant ewes were ovariectomized 3 weeks after mating, and were injected daily with graded doses of progesterone (0·05–1·35 mg./kg.) for the next 6 weeks. A minimum daily dose of 0·15 mg./kg. was found necessary for the regular maintenance of pregnancy. On the 60th day of pregnancy, when the ewes were killed, there was little or no effect of dose of progesterone on foetal weight, weight and number of cotyledons, weight of uterus and membranes or volume of amniotic fluid. However, at the low doses of progesterone the volume of allantoic fluid was about ten times higher than normal, suggesting that progesterone plays some part in the water balance of the conceptus. In treated ewes, the cotyledons tended to be of the bovine type with foetal tissue enveloping the maternal, which suggests that growth of maternal cotyledons may be limited by the absence of ovaries.
It is suggested that the large variations usually observed in the placental size of sheep, are not due to variations in output of ovarian progesterone, and that the normal daily output of the ovine corpus luteum during the first 2 months of pregnancy is equivalent to at least 15 mg. of subcutaneously injected progesterone.
PROLACTIN-LIKE ACTIVITY IN THE PITUITARY GLAND OF THE FROG
Authors: CHADWICK A. 
Published: December 2008

SUMMARY
Homogenates of the distal lobe and combined intermediate and neural lobes from Rana temporaria and R. esculenta and extracts of these lobes, purified by zone electrophoresis in starch gel or by Sephadex column chromatography, were tested for crop-stimulating activity in the pigeon and lactogenic activity in the rabbit. The response of the pigeon crop to injections of homogenates resembled the reaction produced by purified sheep prolactin, but differed in intensity and in the number of fatty 'granules' present. The response in the rabbit differed considerably from the reaction to sheep prolactin. Milk was absent in spite of extensive proliferation in the gland. Injections of purified fractions of the pituitary extracts yielded similar results.
It is concluded that a prolactin-like principle is present in the frog pituitary in both the distal lobe and the combined intermediate and neural lobes which can initiate a prolactin-like response in both the pigeon and the rabbit but cannot bring about the completion of a typical prolactin reaction.
PRESSOR ACTIVITY IN EXTRACTS OF THE CORPUSCLES OF STANNIUS FROM THE EUROPEAN EEL (ANGUILLA ANGUILLA L.)
Authors: JONES I. CHESTER , HENDERSON I. W. , CHAN D. K. O. , RANKIN J. C. , MOSLEY W. , BROWN J. J. , LEVER A. F. , ROBERTSON J. I. S. , TREE M. 
Published: December 2008

SUMMARY
Extracts of corpuscles of Stannius from the silver eel have been shown to contain a substance with a powerful pressor action on intravenous injection into the rat. This material resembles mammalian renin in being non-diffusible through cellophane, heat-labile, and destroyed by acidification to pH 2. The effect in the rat differs, however, from that produced by mammalian renin in being more prolonged, and frequently biphasic.
Pressor activity has also been demonstrated in extracts of kidneys from freshwater silver eels. Incubation of kidney extract with mammalian renin-substrate produced an angiotensin-like pressor substance.
Both renal and corpuscular extracts had a prolonged pressor effect on intravenous injection into the eel. The identities of these pressor materials have not been finally established.
Removal of the corpuscles of Stannius from freshwater silver eels was followed by a drop in blood pressure to levels normally found in eels adapted to seawater.
The possible existence, in the eel, of a renin-angiotensin system analogous to that existing in mammals is discussed.
PROGESTERONE IN SYSTEMIC BLOOD AND PLACENTAE OF INTACT AND OVARIECTOMIZED PREGNANT GUINEA-PIGS
Authors: HEAP R. B. , DEANESLY R. 
Published: December 2008

SUMMARY
Progesterone was isolated from systemic and uterine venous plasma and from placental tissue of intact and ovariectomized pregnant guinea-pigs. It was measured quantitatively by fluorescence assay.
Concentrations of progesterone in intact animals rose from a mean value of 64 ng./ml. plasma 11–16 days post coitum (p.c.) to reach their highest values (265 ng./ml.) 30–45 days p.c. and decreased to 140 ng./ml. immediately before parturition. In pregnant guinea-pigs, ovariectomized 28 days p.c. or later, the progesterone levels were lower (75 ng./ml. at 34–35 days p.c., 146 ng./ml. at 40–45 and 50–55 days p.c.) except at the end of pregnancy (165 ng./ml.). During the last 2 weeks of pregnancy the difference in the progesterone levels of the two groups was not statistically significant.
In ovariectomized pregnant guinea-pigs, the progesterone level was high in the uterine vein but low in placental tissue. The mean wet weight of placentae was, however, significantly correlated with systemic progesterone values.
STUDIES ON THE MECHANISM OF NIDATION XXIII. EFFECT OF ERGOCORNINE IN PREGNANT RATS DURING EXPERIMENTALLY INDUCED DELAYED NIDATION
Authors: VARAVUDHI PUTTIPONGSE , LOBEL BERTHA L. , SHELESNYAK M. C. 
Published: December 2008

SUMMARY
The effects of ergocornine in pregnant rats in which delayed nidation was induced by hypophysectomy and autotransplantation of the pituitary on L1 of pregnancy (i.e. the day following the detection of a copulation plug in the vagina or spermatozoa in the vaginal smear) have been investigated. In the ergocornine-treated animals, no nidation was observed on L13 after a dose of oestrogen triggering implantation had been given on L9. Controls which did not receive ergocornine, or animals which received ergocornine plus progesterone showed implantation sites in a high percentage of cases on L13 after administration of the triggering dose of oestrogen on L9.
No differences were observed between rats in which the pituitary had been transplanted under the kidney capsule and animals in which the pituitary was grafted under the ovarian capsule. In neither case did nidation occur after ergocornine. The possibility is discussed that the action of ergocornine is mediated by the pituitary via the hypothalamus.
THE LOCALIZATION OF [6,7-3H]OESTRADIOL-17β IN RAT UTERUS
Authors: KING R. J. B. , GORDON J. 
Published: December 2008

SUMMARY
The uptake of [6,7-3H]oestradiol-17β (oestradiol) by the rat uterus in vivo has been studied. By pressing uteri between two glass plates much, but not all, of the epithelium is removed with minimal effect on the underlying stroma and myometrium. This procedure removes 11 % of the DNA, 10·6 % of the radioactivity and about 3 % of the wet weight of the intact uterus, indicating that, as judged from the DNA content, there is no accumulation of [6,7-3H]oestradiol in the epithelium relative to the rest of the uterus. In the epithelium, the major portion of the [6,7-3H]oestradiol was in the soluble fraction although a considerable amount of the radioactivity was associated with the nuclei. Similar results were obtained with nuclei isolated by differential or gradient centrifugation. It has been shown that an interchange of [6,7-3H]oestradiol can occur between the nucleus and cytoplasm and that, under the experimental conditions used, the equilibrium favours the cytoplasm.
Some of the [6,7-3H]oestradiol in the soluble fraction from uterine epithelium was associated with a component of high molecular weight that may be a protein.
DETERMINATION OF THE 11β-HYDROXYLASE ACTIVITY IN MICROGRAM SAMPLES OF TISSUE; ITS QUANTITATIVE HISTOLOGICAL DISTRIBUTION IN THE RAT ADRENAL, AND THE INFLUENCE OF CORTICOTROPHIN
Authors: GRIFFITHS K. , GLICK D. 
Published: December 2008

SUMMARY
Recent biochemical studies on the functional zonation of the human adrenal cortex suggest that one of the earlier principal effects of corticotrophin (ACTH) on steroid biosynthesis occurs at the fasciculo-reticular border. This report deals with procedures for the study of the 11β-hydroxylase activity in microgram amounts of adrenal tissue and with the distribution of this activity throughout the adrenal cortex of the rat. ACTH administration is shown to stimulate the 11β-hydroxylase activity at the fasciculo-reticular border.
CORTISOL METABOLISM BY THE ISOLATED AND PERFUSED NEWBORN RABBIT LIVER
Authors: SERENI F. , CASTEGNARO E. , PERLETTI L. , SALA G. 
Published: December 2008

SUMMARY
After perfusion of newborn rabbit liver with [1,2-3H]cortisol two radioactive metabolites were isolated from the perfusate and identified as 3α,11β,17α,21-tetrahydroxy-5β-pregnan-20-one (THF) and 11β,17α,20β,21-tetrahydroxypregn-4-en-3-one (20β-dihydrocortisol). The amount of metabolites recovered in the perfusate of livers of 1-day-old animals was lower than when 11- to 12-day-old animals were used. The results suggest a relative deficiency in the liver of newborn rabbits of the enzyme reducing ring A and the 20-oxo group of cortisol.