bluuebunny/crossref_metadata_2025 huggingface dataset:
THE INDUCTION OF OVULATION BY OVARIAN STEROIDS IN THE ADULT RAT
Authors: BROWN-GRANT K.
Published: December 2008

When oestrogen was administered early in the oestrous cycle of the rat on the day of metoestrus, the inhibitory effect of progesterone injected at dioestrus on ovulation was lost and a facilitatory effect was observed; ovulation was advanced by one day. The advancement of ovulation by oestrogen injected at the dioestrus — 1 stage of a 5-day cycle was confirmed; it was shown that this response could be elicited by as little as 0·13 μg. oestradiol benzoate. These results are discussed in relation to other studies on the time of oestrogen secretion in the normal cycle, the alteration of the response of the pituitary to progesterone injection from an inhibitory to a facilitatory effect by previous exposure to oestrogen, and the mechanism of induction of ovulation by oestrogen in the 5-day cycle and in pregnancy. The relevance of these and similar experiments on the induction of ovulation by ovarian steroids in the rat as a guide to what is occurring during the normal cycle is questioned, principally because when ovulation was induced by these means the changes in the activity of the thyroid gland that are associated with ovulation in the normal cycle were not reproduced.
LUTEINIZING HORMONE LEVELS IN PLASMA AND URINE IN WOMEN DURING NORMAL MENSTRUAL CYCLES AND IN WOMEN TAKING COMBINED CONTRACEPTIVES OR CHLORMADINONE ACETATE
Authors: ORR A. HILARY , ELSTEIN MAX
Published: December 2008

Radioimmunoassay measurements of luteinizing hormone (LH) levels were made in urine and plasma throughout normal menstrual cycles and cycles when either a combined oral contraceptive or low dosage continuous chlormadinone acetate were being taken by healthy young women. The typical mid-cycle ovulatory increase of LH was suppressed in the cycles when the combined contraceptive preparations were taken but was present in the majority of cycles during the administration of continuous chlormadinone acetate.
THE PINEAL GLAND AND LIGHT-INDUCED OESTRUS IN FERRETS
Authors: HERBERT J.
Published: December 2008

Pinealectomy (10 animals) or superior cervical ganglionectomy (14 animals) prevented the acceleration of oestrus in ferrets by two different daily regimes of artificial light. Both sets of animals came into oestrus in the spring following operation at about the same time as normal ferrets kept in daylight. Neither procedure affected the duration of the oestrous period. The interval between onsets of successive postoperative annual oestrous periods in both control-operated and normal animals kept in daylight supplemented by 6 hr. artificial evening illumination was about 1 yr., but was much greater in pinealectomized or ganglionectomized ferrets. An attempt to section the nn. conarii failed to provide direct evidence for a functional link between the superior cervical ganglia and the pineal, but there was a relation between the volume of pineal remaining after this procedure and the activating effect of artificial light on oestrus.
THE AFFERENT PATH OF THE MILK-EJECTION REFLEX IN THE BRAIN OF THE RABBIT
Authors: TINDAL J. S. , KNAGGS G. S. , TURVEY A.
Published: December 2008

The afferent path of the milk-ejection reflex has been studied in the brain of the anaesthetized lactating rabbit. Electrical stimulation was applied between a monopolar electrode in the brain and an indifferent electrode in the scalp. The brain was transected at the mid-cerebellar level to eliminate sympathetico-adrenal activation, and intramammary pressure and arterial blood pressure were monitored to detect release of neurohypophysial hormones.

In the mid-brain, the afferent path of the reflex is compact, lying in the lateral tegmentum of each side and passing forwards to lie medio-ventral to the medial geniculate body. On entering the diencephalon, the pathway on each side bifurcates: a dorsal path passing forwards in association with the extreme rostral central grey and periventricular region, and a ventral path ascending through the subthalamus. The dorsal and ventral paths reunite in the posterior hypothalamus. Delineating the pathway further forward in the hypothalamus, using a simple stimulation technique, was not possible because at this level it intermingles with efferent fibres descending from the paraventricular nucleus to the pituitary stalk. The afferent path of the reflex is concerned with the preferential release of oxytocin from the neurohypophysis, is not a major pathway for the release of vasopressin and its neural substrate in the mid-brain is believed to be the spinothalamic system of fibres.
THE EFFECTS OF CORTISONE ON NITROGEN BALANCE AND GLUCOSE METABOLISM IN DIABETIC AND NORMAL KANGAROOS, SHEEP AND RABBITS
Authors: GRIFFITHS M. , McINTOSH D. L. , LECKIE R. M. C.
Published: December 2008

Alloxan diabetes can be induced in red and in grey kangaroos and the initial changes in blood sugar levels after injection of the drug are similar to those in other herbivores, or in other vertebrates generally.

In general the presence or absence and the severity of catabolic effects of diabetes in rabbits, sheep and red kangaroos all eating the same diet depends on the amount of food eaten.

Injection of large amounts of cortisone into normal rabbits and a sheep induced the usual catabolic effects and injection of cortisone exacerbated the catabolism of diabetic rabbits and diabetic sheep. The same and larger dose rates of cortisone injected into 12 normal and two diabetic red kangaroos had no effect on N balance, hyperglycaemia, food intake, glycosuria, insulin sensitivity, or on intravenous glucose tolerance.
OESTROGEN AND PROGESTERONE CONTENT OF OVARIAN VEIN BLOOD OF THE EWE DURING THE OESTROUS CYCLE
Authors: MOORE N. W. , BARRETT SUSAN , BROWN J. B. , SCHINDLER IRENE , SMITH MARGERY A. , SMYTH BARBARA
Published: December 2008

Ovarian vein blood was collected by cannulating the ovarian vein of 37 ewes at various times during the oestrous cycle. Plasma progesterone and oestrogen concentrations, determined by chemical methods, showed marked cyclic variations during the cycle. Progesterone was detected at all stages of the cycle. Plasma concentrations were rising rapidly by the 4th day after the onset of oestrus and were maintained at levels greater than 100 μg./100 ml. plasma from the 8th to the 14th day of the cycle. They started to fall about 48 hr. before the onset of oestrus. Very low levels, of the order of 1 μg./100 ml. plasma, were maintained from 24 hr. before to 8–16 hr. after the onset of oestrus.

Oestradiol-17β made up almost all of the oestrogens measured. Oestrone accounted for less than one-eighth of the total oestrogens. Oestradiol first appeared on the 14th day of the cycle and its concentration rose rapidly during the immediate pre-oestrous period to reach peak levels of over 100 ng./100 ml. plasma 20–30 hr. before the onset of oestrus. They then rapidly declined and by 24 hr. after the onset had reached almost non-detectable levels.

The ovarian secretion rate of progesterone was calculated to be 3·5 mg./day at mid-cycle and the total secretion of oestradiol during the follicular phase was 4·9 μg. Blood flow through the cannula was not affected by either the stage of cycle at which blood was collected or by the structure (corpus luteum or Graafian follicle) in the ovary bled.
UTERINE MITOSIS, ALKALINE PHOSPHATASE AND ADENOSINE TRIPHOSPHATASE DURING DEVELOPMENT AND REGRESSION OF DECIDUOMATA IN PSEUDOPREGNANT MICE
Authors: HALL KATHLEEN
Published: December 2008

Incidence and patterns of mitoses and histochemical localization of alkaline phosphatase (APase) and adenosine triphosphatase (ATPase) were studied from days 5 to 20 in pseudopregnant mice in which deciduomata had been induced in the left uterine horns by intrauterine injection of oil on day 4, the right horns serving as controls.

In stromal cells, mitoses were very numerous throughout the endometrium of the left (but not the right) horn on days 5 and 6, in the basal, non-decidualized stroma until day 8 or day 9, and were not seen in stromal cells of either horn thereafter. In glandular epithelium, mitoses were absent from days 5 to 10, and numerous from day 11 or 12 until at least day 17 in both horns. Mitoses were present in capillaries within developing deciduomata on days 5 and 6, then seldom seen until day 12 and during the next 3 days were numerous in endothelial and pericapillary cells in the mesometrial quadrant of the left horn and around glands in both horns.

The deciduoma cells reacted strongly with AP and ATP substrates from days 5 to 10, after which the intensity of the reaction weakened and had usually disappeared by day 13. ATPase activity disappeared from vascular endothelium within the deciduoma a few hours after APase had appeared within the deciduoma cells on day 5. It reappeared in the vessel walls on day 9 and thereafter was usually present until the deciduoma was shed. In the basal, non-decidualized stroma, APase was absent until about day 10, then appeared in the stroma cells nearest to the myometrium, extending gradually into the densely packed cells nearest to the regressing deciduoma. The possible role of this enzyme in reparative growth of the endometrium after regression of the deciduoma is discussed.
THE EFFECT OF INSULIN ON THE UTILIZATION OF [U-14C]GLUCOSE AND [1-14C]ACETATE BY GOAT ADIPOSE TISSUE IN VITRO
Authors: ŠKARDA J. , BARTOŠ S.
Published: December 2008

No change in the rate of 14CO2 production from [U-14C]glucose by the adipose tissue of goats was found in vitro, even in the presence of high concentrations of insulin (1 and 10 m-u./ml.) when glucose was the only substrate in the medium. However, it was demonstrated that in the presence of acetate as little as 10 μu. insulin/ml. exerted a marked effect on glucose oxidation. The most significant effect of insulin was that on the rate of [1-14C]acetate incorporation into fatty acids in the presence of glucose. These findings support the suggestion that the significance of insulin in ruminants is best demonstrated by its effects on the rate of utilization of acetate in the presence of glucose by adipose tissue.
EFFECT OF NORETHISTERONE ACETATE, DIMETHYLSTILBOESTROL, GENISTEIN AND COUMESTROL ON UPTAKE OF [3H]OESTRADIOL BY UTERUS, VAGINA AND SKELETAL MUSCLE OF IMMATURE MICE
Authors: FOLMAN Y. , POPE G. S.
Published: December 2008

Both norethisterone acetate and coumestrol enhanced uptake of [3H]oestradiol by the uterus and vagina measured 1 hr. after injection of the two compounds; the effect was, however, transient. Otherwise all the weak utero-vaginotrophic compounds markedly inhibited uptake of [3H]oestradiol by the uterus and vagina. This inhibition and the accompanying growth responses give further support to the conclusion that the interaction in uterine and vaginal tissue between oestradiol and the weaker utero-vaginotrophic compounds studied involves competition for retention at receptor sites followed by expression of the activity characteristic of the compounds retained.
COMPETITIVE BINDING OF FREE AND CONJUGATED OESTROGENS TO PLASMA PROTEINS
Authors: GIORGI ELEONORA P. , CROSIGNANI P. G.
Published: December 2008

Human plasma was dialysed against increasing concentrations of [4-14C]oestradiol-17β, [4-14C]oestrone, Na[6,7-3H]oestradiol-17β-glucuronide and Na[6,7-3H]oestrone sulphate. When the oestrogens were dialysed separately, binding to a protein with a limited number of binding sites (probably a globulin) could be shown. At comparable concentrations oestrone sulphate was bound to a greater extent than the free compounds and the glucuronide.

When free and conjugated oestrogens were dialysed together a displacement of the conjugates from globulin to albumin was demonstrated. This observation was confirmed by the results of the equilibrium dialysis of plasma of ovarian vein blood obtained from a mare and a donkey after injection of [4-14C]oestradiol-17β and Na[6,7-3H]oestradiol-177β-glucuronide into a Graafian follicle of the homolateral ovary. The possible physiological significance of this competition between free and conjugated oestrogens is discussed.
CARDIOVASCULAR CHANGES DURING LACTATION IN THE RAT
Authors: CHATWIN A. L. , LINZELL J. L. , SETCHELL B. P.
Published: December 2008

The effect of lactation on cardiac output, measured by Fegler's thermodilution technique, and on organ blood flow, measured by Sapirstein's indicator fractionation technique, has been investigated by studying three groups of rats: (1) on day 1 of lactation; (2) on day 12 of lactation, suckling a large litter; (3) on day 12, the young having been removed on day 1. Lactation was accompanied by a significant increase in the weight of the mammary glands, the liver and the small and large intestines and a decrease in the weight of the female reproductive tract and of the skin. Cardiac output in 12-day lactating animals was significantly higher than in non-lactating and in rats on day 1. The proportion of the cardiac output taken by the mammary glands, liver, gastrointestinal tract and their blood flow/g. tissue, increased. Skin blood flow increased, but not that of brain, heart or kidney.
METABOLISM OF DEHYDROEPIANDROSTERONE BY THE SEPARATED ZONES OF THE HUMAN FOETAL AND NEWBORN ADRENAL CORTEX
Authors: SHIRLEY I. M. , COOKE B. A.
Published: December 2008

An ultramicrochemical technique has been applied to the study of the metabolism in vitro of [3H]DHA in the separated adult and foetal zones of the human adrenal gland. Evidence has been found for the formation of DHA sulphate and androstenedione in the adult and foetal zone, and whole adrenal gland preparations obtained from one newborn hydrocephalic infant and two mid-term foetuses, and also for the formation of 1 1β-hydroxyandrostenedione in the adult zone tissue from the hydrocephalic infant. In all experiments, more DHA was converted to DHA sulphate by the foetal zone (21–27% conversion) than by the adult zone (5–7% conversion), whereas more androstenedione was formed in the adult zone than in the foetal zone. At mid-term less than 0·6% of [3H]DHA was converted to androstenedione compared with 33 and 3·4% conversion by the adult and foetal zone tissue, respectively, from the hydrocephalic infant.

These results are discussed in relation to perfusion studies of the human foetus and previous in vitro and histochemical investigations of the human foetal adrenal gland.
THE INFLUENCE OF THE OVARIAN HORMONES ON THE ACTOMYOSIN CONTENT AND THE DEVELOPMENT OF TENSION IN UTERINE MUSCLE
Authors: MICHAEL C. A. , SCHOFIELD BRENDA M.
Published: December 2008

Actomyosin concentrations and tensions were measured in the rabbit uterus during pregnancy and in ovariectomized hormone-treated animals. The results showed that actomyosin concentration and tension in g./mm.2 longitudinal muscle followed similar courses during pregnancy. This was not so in the hormone-treated animals. Small quantities of oestrogen were sufficient in ovariectomized animals to produce a major difference between the untreated and treated animals. With higher doses only the concentration of the actomyosin increased linearly.

During pregnancy a significant correlation was found between the number of foetuses in each horn, the quantity of actomyosin and the weight of the horn.

The major increase in tension and actomyosin concentration occurred in the last half of pregnancy when the increase in uterine volume accelerates. The importance of this growth, as opposed to hormonal environment, was further emphasized by experiments in unilaterally pregnant rabbits in which both these quantities were significantly greater in the parous horn than in the non-parous horn.

The effects of progesterone were also investigated.
ASSESSMENT OF A TEST OF ADRENOCORTICAL FUNCTION USING β1–25 CORTICOTROPHIN
Authors: WHALEY K. , SOUTTER W. P. , DICK W. C. , NUKI G. , DOWNIE W. W.
Published: December 2008

In ten patients with a variety of rheumatic disorders the changes in plasma corticosteroid (11-OHCS) levels have been studied after adrenocortical stimulation by a continuous 5 hr. infusion of Synacthen (Ciba) or by a single i.v. injection of 200 i.u. (320 μg.) Pentacosactride (Sandoz). Comparable increases were obtained using both synthetic polypeptides. It is suggested that administration of Pentacosactride intravenously is a simple method of obtaining prolonged maximal stimulation of the adrenal cortex. A normal range of values of plasma 11-OHCS, obtained from 28 subjects, is given, and it is shown that the results are reproducible. The results of tests in six subjects with secondary adrenal atrophy due to long-term corticosteroid therapy indicate that the test can discriminate between normal and subnormal adrenocortical function.
CORTICOSTEROID SYNTHESIS IN VITRO BY ADRENAL TISSUE FROM NEWBORN ANENCEPHALIC INFANTS
Authors: SHAHWAN M. M. , OAKEY R. E. , STITCH S. R.
Published: December 2008

Adrenal tissue from newborn anencephalic infants converted pregnenolone and progesterone to cortisol, 17α-hydroxyprogesterone, corticosterone, 17α,21-dihydroxyprogesterone, deoxycorticosterone and 1 1β-hydroxyprogesterone in vitro. These metabolites were identified by recrystallization to constant specific activity after multiple chromatography and derivative formation. The results demonstrate a potential for corticosteroid biosynthesis, at least from pregnenolone and progesterone, by the adrenals of the anencephalic infant, and therefore possibly by the definitive zone of the adrenal of the normal newborn infant.
EFFECTS OF OVARIAN STEROIDS ON THE NORETHISTERONE-BLOCKADE OF OVULATION IN THE RAT
Authors: McDONALD P. G. , GILMORE D. P.
Published: December 2008

In the majority of normal cycling female rats, a single injection of norethisterone (0·5 mg.) delayed ovulation by 24 hr. The number of animals showing delayed ovulation was dependent upon the stage of the cycle and the time of day at which the steroid was given. Injection on day 1 (oestrus) and day 3 (dioestrus 2) was most effective (80% delay) followed by day 2 (dioestrus 1, 50% delay) and day 4 (pro-oestrus, 0% delay). Oestradiol benzoate (5 μg.) given to norethisterone-treated rats on day 3 largely overcame the delaying action of the steroid. Similarly the injection of progesterone (1 mg.) on day 4 advanced ovulation by 24 hr. in most of the norethisterone-treated rats. It is suggested that norethisterone exerts its effects at both pituitary and hypothalamic levels.
THE RELEASE OF ANTIDIURETIC HORMONE FROM THE PITUITARY STALK AFTER INTRAVENOUS CALCIUM CHLORIDE OR MAGNESIUM CHLORIDE INFUSION IN RATS
Authors: LEŚNIK HELENA , GUZEK J. W. , TRACZYK W. Z.
Published: December 2008

Experiments were performed on male albino rats in urethane anaesthesia. The pituitary gland was exposed, the pituitary stalk was cut and the whole gland was removed. Isotonic sodium chloride solution used for washing the cut pituitary stalk was collected and its antidiuretic activity assayed. Antidiuretic substance was liberated from the infundibular axons into the washing fluid during continuous intravenous infusion of a hypotonic saline. The antidiuretic activity of the washing fluid was assayed in ethanol-anaesthetized rats. A 5% sodium chloride solution, infused intravenously to the limit of 1% of the body weight, caused a significant release of antidiuretic substance from the cut infundibular axons. A similar effect was observed after the i.v. infusion of 1 ml. of a solution containing 0·06 mm-CaCl2. The i.v. infusion of 0·02 mm-MgCl2 decreased the amount of antidiuretic substance liberated from the pituitary stalk significantly.
PRESSOR EFFECTS OF NEUROHYPOPHYSIAL PEPTIDES IN THE EEL, ANGUILLA ANGUILLA L., WITH SOME REFERENCE TO THEIR INTERACTION WITH ADRENERGIC AND CHOLINERGIC RECEPTORS
Authors: CHAN D. K. O. , JONES I. CHESTER
Published: December 2008

In the European eel, Anguilla anguilla L., neurohypophysial peptides caused prolonged, dose-dependent, increases in blood pressure in the ventral aorta but decreased that in the dorsal aorta. In order of potency they were: isotocin, oxytocin, arginine vasotocin and arginine vasopressin. Lysine vasopressin was without appreciable effects.

Depletion of adrenergic stores in the animal by pharmacological means or blockade of α-adrenergic receptors reduced or abolished the pressor response in the ventral aorta. Partial tachyphylaxis to the peptides could be restored by injection of noradrenaline. Blockade of cholinergic receptors abolished the postbranchial vasodepressor effect. Thioglycerol attenuated the pressor response. The possible mechanism of action of neurohypophysial peptides with special reference to the unifying concept of increases in membrane permeability is discussed.
CHANGES IN BLOOD GLUCOSE AND LIVER CARBOHYDRATE AFTER INTRAUTERINE INJECTION OF GLUCAGON INTO FOETAL RATS
Authors: HUNTER D. J. S.
Published: December 2008

Maternal blood glucose, foetal blood glucose and liver carbohydrate levels were estimated after foetuses were injected with glucagon through the uterine wall on days 19½, 20½ and 21½ of gestation in the rat.

Glucagon had a hyperglycaemic effect in the foetus on all the days studied but the response was greater and more rapid on day 21½ of gestation. Glucagon was shown to decrease liver glycogen on day 20½ and 21½ but again the response was more rapid and more pronounced on day 21½.

The normal levels of foetal liver glycogen were similar to those previously found but the normal foetal blood glucose values are lower than previous results. Decrease in liver glycogen observed in the control group of foetuses on day 21½ of gestation together with a loss in foeto-maternal blood glucose relationship on that day of gestation suggest that on day 21½ the foetal rat develops the ability to mobilize hepatic glycogen and thereby to alter its blood glucose level independently from the mother.

The significance of the low blood glucose levels found in the foetus is discussed.
THE EFFECT OF PARATHYROID EXTRACT ON CELLULAR ACTIVITY AND PLASMA CALCIUM LEVELS IN VIVO
Authors: BINGHAM PATRICIA J. , BRAZELL IRIS A. , OWEN MAUREEN
Published: December 2008

Parathyroid hormone has a direct effect on the osteoclast population present at the time of administration of the hormone. There was a significant stimulation of nuclear RNA synthesis at the earliest time (1½ hr.) at which the measurement could be made. This is followed by increased production of cytoplasmic RNA which reaches its maximum after a considerable time-lag (7 to 12 hr. after parathyroid extract (PTE)). The increase in cytoplasmic RNA is accompanied by a corresponding stimulation of protein and mucoprotein synthesis in the osteoclasts and the effect persists at least until 24 hr. This time-lag and the relatively long duration of the effect on protein synthesis can be correlated approximately with the effect on the plasma calcium level. It is suggested therefore that the rise in plasma calcium is mainly due to the increased cellular activity of the osteoclasts and the resulting increased bone resorption. The opposite effect on the osteoblast system has about the same time-sequence and would complement the effect on the osteoclast system. At about the same time as the maximum increase in cellular activity in the osteoclasts is observed, a significant effect on RNA synthesis in the endosteal mesenchymal cells, the precursors of the osteoclasts, becomes apparent. This is closely followed by a rise in the number of osteoclasts which is first apparent at 17 hr. after PTE and is maximal by 24 hr. Consequently, the rise in the number of osteoclasts is a secondary effect and is not responsible for the initial rise in plasma calcium which occurred much earlier. It is suggested that the increase in osteoclast numbers follows as a result of the increased metabolic activity of the osteoclast population present when the hormone was injected.

There is a depression of RNA synthesis in both the osteoblasts and their precursors, the preosteoblasts. This means that the hormone has opposite effects, not only on the osteoblasts and osteoclasts, but also on their respective precursors, indicating that osteoprogenitor cells contain a mixture of cells with two main lines, those differentiating in an osteoblastic or osteoclastic direction, respectively.
THE MITOGENIC ACTION OF OVARIAN HORMONES ON THE UTERINE AND THE VAGINAL EPITHELIUM DURING THE OESTROUS CYCLE IN THE RAT: A RADIOAUTOGRAPHIC STUDY
Authors: LEROY F. , GALAND P. , CHRÉTIEN J.
Published: December 2008

Mitotic parameters (S phase duration and generation time) have been studied in the vaginal and the endo-uterine epithelium, at different stages of the oestrous cycle in the rat. The double labelling technique with [3H]thymidine was employed. Both in the vaginal basal epithelial layer and in the endometrial epithelium the cellular proliferation rate was maximal during dioestrus, whereas the longest generation times were observed at oestrus. This finding is in accordance with the recently proposed pattern of oestrogen secretion in this species. Maximal growth rate in the vagina was delayed as compared with the uterine epithelium.
PROGESTERONE CONCENTRATION IN THE PERIPHERAL PLASMA OF SHEEP DURING THE OESTROUS CYCLE
Authors: THORBURN G. D. , BASSETT J. M. , SMITH I. D.
Published: December 2008

Using a protein-binding technique, progesterone concentrations in peripheral plasma (jugular vein) were measured throughout the oestrous cycle of 24 ewes. Examination of the specificity of the method by thin-layer chromatography indicated that interference from other steroids was not significant in sheep plasma. During the first 4 days of the cycle (days 0–3), plasma progesterone concentrations were below 0·4 ng./ml., increasing to a mean level of 1·5–2·5 ng./ml. between days 4 and 9, and remaining at this level for approximately 5 days, before declining rapidly on days 14 and 15 to reach a low level on the day before oestrus. The progesterone concentration on the day of oestrus was extremely low (0·1 ng./ml.), and was of the same order as that found in the plasma of wethers and anoestrous or ovariectomized ewes. Three ewes, superovulated with pregnant mare serum gonadotrophin, showed marked elevation of peripheral progesterone concentration during the luteal phase of the cycle, the concentration being proportional to the number of corpora lutea formed.
THE EFFECT OF FREE FATTY ACIDS ON RESIN UPTAKE OF TRI-IODOTHYRONINE FROM HUMAN, RAT, RABBIT AND GUINEA-PIG SERUM AND HUMAN SERUM ALBUMIN
Authors: NATHANIELSZ P. W.
Published: December 2008

Recently changes in plasma free fatty acids have been suggested as a possible regulator of the levels of free thyroxine in the plasma. Oleic acid has been shown to displace tri-iodothyronine from human serum, human serum albumin, rat serum, rabbit serum and guinea-pig serum. The extent of the displacement, much greater from human serum albumin than from whole serum, suggests that free fatty acid does not affect the globulin binding site. It would also appear that, in the rat, all the binding sites are sensitive to free fatty acids and hence there is probably only albumin binding in this species. The results with rabbit and guinea-pig serum were intermediate to those with human and rat serum. A significant rise in resin uptake of tri-iodothyronine in vitro occurred with an increase of free fatty acid level of 0·5 m-equiv./l., well within the physiological range.
PROLACTIN ACTIVITY OF SHORT-TERM AND LONG-TERM AUTOGRAFTED PITUITARIES OF THE HYPOPHYSECTOMIZED CRESTED NEWT
Authors: PEYROT A. , MAZZI V. , VELLANO C. , LODI G.
Published: December 2008

The transplanted pituitary is able to trigger water drive in estivating hypophysectomized adult newts up to 140 days after the operation. Both in short-term (30 days) and long-term (140 days) operated animals the grafted pituitary produced significantly more prolactin than in controls. The results indicate that in the estivating crested newt prolactin production is under an inhibitory neural control and that a short feedback control is not exerted by prolactin itself on the grafted pituitary.
A SOLUBLE ANDROGEN RECEPTOR IN THE CYTOPLASM OF RAT PROSTATE
Authors: MAINWARING W. I. P.
Published: December 2008

A thermolabile protein with the properties of a steroid 'receptor' was identified in the cytoplasmic or 105,000 g supernatant fraction of the rat prostate. The receptor has a particular binding specificity towards 5αdihydrotestosterone. Testosterone is bound to a lesser extent but other steroids, including certain androgenic hormones, are not bound. The sedimentation coefficient of 8·0 s and the frictional ratio of 1·96, equivalent to a molecular weight of 2·74 × 105, clearly distinguish the soluble androgen-receptor from the androgen-binding globulin in serum and the androgen-receptor in the prostatic nucleus. Like the nuclear receptor, however, the soluble receptor is probably an acidic protein. Both cysteine and tryptophan residues appear necessary for maintaining the functional configuration of the receptor.
THE INCORPORATION OF 131I-IODINATED HUMAN SERUM ALBUMIN IN THE OVARY AND UTERUS BEFORE IMPLANTATION IN THE MOUSE
Authors: BINDON B. M.
Published: December 2008

The uptake of 131I-iodinated human serum albumin ([131I]HSA) by the ovary and uterus was used as an indicator of capillary permeability in these organs from pro-oestrus through to day 5 of pregnancy. Highest levels of [131I]HSA in the ovary were found on the day of pro-oestrus. Ovarian uptake declined significantly on days 1 and 2, then rose to an abrupt and transient peak at 17.00 hr. on day 3. The two peaks of ovarian uptake coincide with the appearance of ovarian hyperaemia.

Uterine incorporation of [131I]HSA was high at pro-oestrus and declined significantly on days 1 and 2. The first significant increase occurred between 09.00 hr. and 17.00 hr. on day 3 and a further increase was observed between days 4 and 5. Only the pro-oestrous peak was associated with observable uterine hyperaemia.
SOME ASPECTS OF THE MEASUREMENT OF CORTISOL PRODUCTION IN PATIENTS WITH BREAST CANCER
Authors: DESHPANDE N. , JENSEN VIBEKE , CARSON PAMELA , BULBROOK R. D. , LEWIS A. A.
Published: December 2008

The production rate of cortisol based on both the plasma clearance of the hormone (plasma production rate) and the urinary metabolite method (urinary production rate) was simultaneously measured in early or advanced breast cancer patients and in controls. Higher production of the hormone was observed by both these methods in patients with advanced breast cancer.

There was a significant correlation between the plasma production rate of cortisol and its urinary production based on the specific activities of three urinary metabolites, namely, cortisol, tetrahydrocortisol (THF) and tetrahydrocortisone (THE). However, the values obtained for the urinary production rate differed considerably in about one-third of the patients due to differences in the specific activities of THE and THF. It is postulated that, in some cases, there may be a second precursor of urinary THE and THF which contributes significant amounts to the excretion of these metabolites.

No correlation was found between the cortisol production rate and urinary total 17-hydroxycorticosteroids (17-OHCS).
OXYTOCIN AS A NEUROHYPOPHYSIAL HORMONE IN THE HOLOCEPHALIAN ELASMOBRANCH FISH, HYDROLAGUS COLLEI
Authors: PICKERING B. T. , HELLER H.
Published: December 2008

Two peptides with uterotonic activity have been isolated from the pituitary gland of a holocephalian elasmobranch fish: Hydrolagus collei. One of them had an amino acid composition compatible with that of oxytocin itself, and also had the pharmacological properties of this hormone. The other peptide which was present in much smaller amounts was basic by chromatography and had the pharmacological characteristics of [8-arginine]-oxytocin. It was not completely purified because of the small amount available, but its amino acid composition was in accord with that of vasotocin. The implications of the presence of oxytocin in such a primitive fish on the phylogeny, and hence probably the evolution, of neurohypophysial hormones are discussed.
RECEPTIVITY SCORES OF FEMALE RATS STIMULATED EITHER MANUALLY OR BY MALES
Authors: GERALL A. A. , McCRADY R. E.
Published: December 2008

Receptivity ratings of female rats that had been injected neonatally with either sesame oil or varying amounts of testosterone propionate (TP) were compared, using either a currently used manual technique or males as the test stimuli. Females receiving more than 10 μg. TP when 5 days old either rejected the male or gave minimal lordotic responses when mounted. However, they often responded with complete lordosis when manually stimulated. Untreated females in heat tended to obtain higher receptivity ratings with males than with the manual stimulus. In general, manual test ratings were found to be less related to oestrous conditions than those recorded with males. Some of the limitations and advantages of each method are discussed.
A COMBINED ISOTOPIC AND ELECTRON MICROSCOPIC STUDY OF THE RESPONSE OF THE RAT UTERUS TO EXOGENOUS OESTRADIOL
Authors: HAM KATHRYN N. , HURLEY J. V. , LOPATA A. , RYAN G. B.
Published: December 2008

Experiments with 131I-labelled albumin showed that the injection of oestradiol-17 β induces massive escape of fluid with a protein content similar to that of plasma into the extravascular tissue of the uterus of immature female rats. Histological and electron microscopic examination confirmed the increased permeability to protein of uterine blood vessels, and showed its morphological basis to be the appearance of transient and reversible gaps in the normally complete endothelial lining of capillaries and small venules. These gaps were similar to those seen in small blood vessels in acutely inflamed tissues.

The ultrastructural appearance of endothelial cells was unchanged in the early phase of the response to oestrogen, but 24–48 hr. later there was electron microscopic evidence of both growth and marked secretory activity of endothelial cells. The nature of the material secreted, if any, has not been determined.
THE INFLUENCE OF OESTROGEN AND PROGESTERONE ON SPERM CAPACITATION IN THE REPRODUCTIVE TRACT OF THE FEMALE RABBIT
Authors: BEDFORD J. M.
Published: December 2008

Using the techniques of sperm transfer into the oviduct of recipient females, or ovum transfer to the site of capacitation, it has been shown that the capacitating activity of the female genital tract may be modified by oestrogen and by progesterone. The normal capacitating potential of the Fallopian tube is diminished after ovariectomy, and is restored by oestrogen injection. In the absence of oestrogen (in the ovariectomized and adrenalectomized female) this activity is still maintained at a basal level sufficient to capacitate the numbers of sperm which normally enter the Fallopian tube after coitus. Capacitation is not significantly disturbed in the Fallopian tube of the intact progesterone-dominated female (Chang, 1958), and the innate basal capacitating activity persists in the Fallopian tubes of ovariectomized females treated with progesterone.

The ability of the uterus to bring about complete capacitation is lost in the progesterone-dominated female. Sperm are completely capacitated in about 11 hr. in the oestrous uterus, but only partial capacitation occurred during this period in the uterus of the ovariectomized rabbit. As judged by the time of penetration of eggs placed into the uterus at different times after insemination, sperm in the ovariectomized uterus did not acquire the capacity to fertilize for approximately 20 hr. Injection of up to 1000 i.u. human chorionic gonadotrophin at the time of insemination did not result in significant depression of capacitation in the uterus.

It is concluded that the rabbit oviduct has a greater innate potential for capacitation than the uterus, though this potential is increased in both sites by oestrogen stimulation. In contrast to its depressive effect on capacitation in the uterus, progesterone apparently does not significantly affect capacitation in the oviduct, even in the absence of the ovaries. This implies that modification of the endocrine status of the female rabbit would not produce a total contraceptive block of capacitation per se.
THE EFFECT OF INGESTION OF HYPERTONIC SALINE ON THE MELANOCYTE-STIMULATING HORMONE CONTENT AND HISTOLOGY OF THE PARS INTERMEDIA OF THE RAT PITUITARY GLAND
Authors: HOWE A. , THODY A. J.
Published: December 2008

The changes in the content of melanocyte-stimulating hormone (MSH) and histology of the neuro-intermediate (n.i.) lobe were followed in rats which drank 2% sodium chloride for periods from 1–15 days.

The pars intermedia showed a biphasic response. During the initial phase of 1–4 days there was a rapid rise in the MSH content, by 153% in the first day, falling back to control level by 4 days. These fluctuations were paralleled by an increase in the normally small numbers of Type 2 cells and at the same time numerous Type I cells showed hypertrophy and degranulation.

After 4 days on saline there was a second rise in the MSH content, which was still evident at 15 days; during this second period the number of Type 2 cells declined to normal levels. The degranulated Type 1 cells also disappeared, most of Type 1 being smaller in size and intensely PAS-positive.

After the ingestion of saline it apparently takes several days before the pars intermedia adapts to a new level of activity.

The likely significance of these changes and the possibility of a relationship between the pars intermedia and the neurohypophysis are discussed.
PROLONGED ACTIVITY IN VIVO OF RABBIT ANTISERA TO PLACENTAL GONADOTROPHINS
Authors: BINDON B. M.
Published: December 2008

Antisera were raised to pregnant mare serum gonadotrophin (PMSG) and human chorionic gonadotrophin (HCG) in male rabbits. The biological potencies of the antisera, A-PMSG and A-HCG, were determined against homologous antigens PMSG and HCG, using the mouse uterus test in immature mice.

A single injection of A-PMSG was shown to inhibit the response to PMSG when injected as late as 21 days after the antiserum. The duration of inhibition was shown to depend on the dose of antiserum injected. These results were confirmed in hypophysectomized mice.

A-HCG was shown to cause similar prolonged inhibition of the response to HCG in intact mice.

The results suggest that A-PMSG and A-HCG persist in the circulation of the mouse for periods of time expected on the basis of the known half-life of rabbit γ-globulin (5 days).
INFLUENCE OF ADRENALECTOMY IN FEMALE RATS ON REPRODUCTIVE PROCESSES INCLUDING EFFECTS ON THE FOETUS AND OFFSPRING
Authors: THOMAN EVELYN B. , SPROUL MYRNA , SEELER BARBARA , LEVINE S.
Published: December 2008

Mating and impregnation were not prevented by adrenalectomy in female rats; they carried their young to term, large litters of viable young were born and lactation was sufficient to maintain the young throughout the usual nursing period. By comparison with sham-operated mother rats, the adrenalectomized mothers gave birth to smaller litters, their pups weighed less and had increased levels of plasma corticosterone.

Prenatal and postnatal effects on the offspring were separated by crossfostering procedures. At 21 days of age there was no significant difference among the groups in the number of pups surviving; however, the pups weighed less if the biological or foster mother was adrenalectomized. These differences were less marked in multiparous mothers.
INDUCTION OF OVULATION IN SHEEP BY ELECTRICAL STIMULATION OF HYPOTHALAMIC REGIONS
Authors: PRZEKOP F. , DOMAŃSKI E.
Published: December 2008

Electrical stimulation of the anterior hypothalamus (regions of the supraoptic and anterior hypothalamic nuclei) or of the ventro-medial hypothalamus (infundibular or ventro-medial nuclei) during the last month of anoestrus in ewes induced ovulation within 72 hr., while similar stimulation of the same centres during the breeding season on the 12th day of the oestrous cycle did not advance ovulation. The role of the hypothalamic centres in the control of gonadotrophin secretion and ovulation is discussed in the light of these results.
THE INFLUENCE OF PITUITARY HOMOGRAFTS ON THE WEIGHT OF THE ACCESSORY REPRODUCTIVE ORGANS IN CASTRATED MALE MICE AND RATS AND ON MATING BEHAVIOUR IN MALE MICE
Authors: BARTKE A. , LLOYD C. W.
Published: December 2008

The effects of heterotopic pituitary homografts on the weight of the accessory reproductive structures, submandibular glands and kidneys were studied in castrated, castrated—adrenalectomized and castrated—hypophysectomized male rats and mice. In rats no consistent effects were seen; in mice the weights of the seminal vesicles, submandibular glands and kidneys were increased. When castrated mice were treated with prolactin or growth hormone (GH), singly or combined, the seminal vesicles responded to all three treatments at certain dose levels, while the submandibular glands were affected by GH only. The effects of pituitary isografts were compared in castrated and in intact hereditary dwarf mice. The weight of the submandibular glands was increased in both groups but that of the seminal vesicles only in intact dwarfs. It was concluded that in male mice prolactin exerts a small testis-independent influence on the reproductive system, and may also increase the production of androgen by the testis. Pituitary grafts had no effect on the restoration of mating behaviour in either castrated or castrated—hypophysectomized male mice treated with testosterone propionate.
EVALUATION OF A RAPID METHOD FOR THE MEASUREMENT OF PLASMA PROGESTERONE BY COMPETITIVE PROTEIN BINDING
Authors: MARTIN B. T. , COOKE B. A. , BLACK W. P.
Published: December 2008

A competitive protein-binding method for the measurement of progesterone in plasma of human subjects was investigated. The purification steps necessary to achieve good accuracy, precision and specificity were determined. It was found that one paper chromatographic separation of unwashed ethyl acetate plasma extracts was sufficient, providing that the sample contains a minimum of 1 ng. progesterone. Water blank values equivalent to 0·05 ng. progesterone were consistently obtained. The concentrations of progesterone found in plasma during the follicular and luteal phases of the menstrual cycle and in male plasma were 0·14 ± 0·14, 0·82 ± 0·74 and 0·022 ± 0·015 (s.d.) μg./100 ml., respectively.
THE METABOLISM OF BETAMETHASONE
Authors: BUTLER JOAN , GRAY C. H.
Published: December 2008

The metabolism of [3H]betamethasone has been studied in normal subjects and in patients receiving high therapeutic doses of the steroid. About 70% of the dose was excreted in the urine in 48 hr.; 15–30% of the dose was found in the unconjugated fraction. Six metabolites as well as unchanged betamethasone were isolated and identified by paper chromatography using reference compounds prepared from [3H]betamethasone. The transformations were: oxidation of the 11β-hydroxyl group, hydroxylation at the 6β-position, reduction of the carbonyl group at C-20 and removal of the side chain to give 17-oxosteroids.
NEUTRAL STEROID SULPHATES IN AMNIOTIC FLUID
Authors: LUUKKAINEN T. , SIEGEL A. , VIHKO R.
Published: December 2008

Steroid monosulphate and disulphate fractions were obtained by chromatography on Sephadex LH-20 from human amniotic fluid collected at term. Only 16α-hydroxydehydroepiandrosterone could be identified in the monosulphate fraction, the detection limit being 5–8 μg./1000 ml. amniotic fluid. In the disulphate fraction 5-androstene-3β,17α-diol, 5-androstene-3β,17β-diol, 5-pregnene-3β,20α-diol, 5α-pregnane-3β,20α-diol, 16α-hydroxydehy-droepiandrosterone, 16β-hydroxydehydroepiandrosterone, 3β, 17β-dihy-droxy-5-androsten-16-one and 5-pregnene-3β,17α,20α-triol were identified by gas—liquid chromatography and gas chromatography—mass spectrometry. The concentrations of these steroids were determined in a pool of human amniotic fluid taken at term. The main compound was 5-androstene-3β,17α-diol.
SITES OF FORMATION OF FRUCTOSE, CITRIC ACID AND SIALIC ACID IN THE ACCESSORY GLANDS OF THE GIANT FRUIT BAT, PTEROPUS GIGANTEUS GIGANTEUS (BRÜNNICH)
Authors: RAJALAKSHMI M. , PRASAD M. R. N.
Published: December 2008

The morphology of the male genital tract and the sites of formation of fructose, citric acid and sialic acid in the male accessory glands of the giant fruit bat, Pteropus giganteus giganteus are described. The seminal vesicle secretes only fructose while the prostate and ampullary glands secrete both fructose and citric acid. Cowper's glands secrete large amounts of sialic acid. However, considerable variations in content and concentration of these constituents are found within the group.
THE FAILURE OF PROGESTERONE TO AFFECT MYOMETRIAL ACTIVITY IN THE GUINEA-PIG
Authors: PORTER D. G.
Published: December 2008

A study was made of the effects of both systemic and intrauterine progesterone and medroxyprogesterone acetate (MPA) administration on the duration of pregnancy in the guinea-pig. In no case was pregnancy prolonged beyond normal term. When progesterone and MPA were administered to non-pregnant guinea-pigs (in doses up to 50 times that required to block myometrial activity in the rabbit) there was no effect on the amplitude and frequency of intrauterine pressure cycles recorded in vivo by means of intrauterine balloons. The response of the uterus to a standard dose (20 m-u.) of oxytocin was unchanged by progesterone. The administration of progesterone by an intrauterine, instead of a systemic, route did not alter the result. It is concluded that progesterone is not a myometrial blocking agent in the guinea-pig.
SURVIVAL AND FUNCTIONING OF AUTOPLASTIC, HOMOPLASTIC AND XENOPLASTIC PITUITARY GRAFTS IN THE RED-SPOTTED NEWT
Authors: DENT J. N.
Published: December 2008

Hypophysectomized red-spotted newts [Notophthalmus (Triturus, Diemictylus) viridescens viridescens Rafinesque] received autoplastic, homoplastic or xenoplastic grafts of pituitary glands beneath the lower jaw.

Autografted animals, in accord with previous observations, survived indefinitely. Homografted animals had a mean survival time several times longer than either that of unimplanted, hypophysectomized animals or that of homografts of skin. No difference between rates of iodine turnover was found between thyroid glands of animals with homografts and animals with autografts but in both groups the rates of iodine turnover were lower than in intact controls.

Great variation was found among the mean survival times of animals with xenografts. Newts with pituitary grafts from the frog, Rana pipiens, survived about as long as unimplanted hypophysectomized animals. Pituitary grafts from the salamander, Desmognathus monticola, apparently gave rise to some toxic reaction since their host newts died within short periods of time, yet newts with grafts from the mudpuppy, Necturus maculosus, lived longer than hypophysectomized control animals and some newts grafted with glands from a west coast newt, Taricha torosa, lived indefinitely.
THE EFFECT OF A HIGH-PROTEIN DIET ON PLASMA GLUCOSE CONCENTRATION, INSULIN SENSITIVITY AND PLASMA INSULIN IN RATS
Authors: BLÁZQUEZ E. , QUIJADA C. LÓPEZ
Published: December 2008

The administration of a high-protein diet to rats, from the end of lactation until they reached a weight of 150 g., produced significant changes in the concentrations of insulin in the plasma and pancreas. Compared with controls, the animals receiving this diet had higher plasma glucose and insulin concentrations and a higher hormone content in the pancreas.

The levels of hepatic glycogen were similar to those in the control rats, but the muscle glycogen was significantly lower. Adipose tissue in vitro was less sensitive to the action of insulin on glucose uptake.