bluuebunny/crossref_metadata_2025_split huggingface dataset:
PLACENTAL LACTOGEN (CHORIONIC MAMMOTROPHIN) IN THE FIELD VOLE, MICROTUS AGRESTIS, AND THE BANK VOLE, CLETHRIONOMYS GLAREOLUS
Authors: FORSYTH ISABEL A. , BLAKE LAURA A. 
Published: December 2008

SUMMARY
Placental lactogen has been detected in the field vole, Microtus agrestis, and the bank vole, Clethrionomys glareolus, using a co-culture technique. In field voles this activity could be detected from about day 8 of pregnancy to shortly before term, and stimulated both mouse and vole mammary gland to secrete in vitro. Partial immunological cross-reaction was detected in a radioimmunoassay system between rat prolactin and either extracts of vole pituitaries or media on which vole pituitaries had been cultured; vole placental lactogen showed no cross-reaction with rat prolactin. One site of origin for this hormone is probably the trophoblastic giant cells.
EFFECT OF INTRA-UTERINE FOREIGN BODIES AND OF PROSTAGLANDIN ADMINISTRATION ON PROGESTERONE SECRETION DURING THE OESTROUS CYCLE OF THE GUINEA-PIG
Authors: BLATCHLEY F. R. , DONOVAN B. T. 
Published: December 2008

SUMMARY
The response of the guinea-pig corpus luteum to the luteolytic influence of glass beads placed in the uterus, or to prostaglandin administration, was followed by assay of the progesterone content of blood samples collected daily. Following the introduction of glass beads into the uterus early in the cycle, the secretion of progesterone was curtailed. Treatment with prostaglandin F2α over days 4–6 or 6–8 of the cycle temporarily depressed progesterone release without shortening the life of the corpora lutea. When the drug was administered over days 8–10, 10–12 or 12–14 the depression in progesterone was not followed by any recovery.
These observations indicate that the response of the corpora lutea to a luteolytic influence changes during the oestrous cycle.
RENIN, CORTISOL AND PLASMA VOLUME IN MARINE TELEOST FISHES ADAPTED TO DILUTE MEDIA
Authors: NISHIMURA HIROKO , SAWYER W. H. , NIGRELLI R. F. 
Published: December 2008

SUMMARY
The renin–angiotensin system has been found in teleost fishes from both marine and freshwater environments. In an attempt to define whether activity of the renin–angiotensin system is related to sodium balance in fishes, we transferred two euryhaline teleosts from seawater to hypo-osmotic media. Plasma renin activity decreased in American eels, Anguilla rostrata, after they were transferred from seawater to fresh water, and it did not change in the aglomerular toadfish, Opsanus tau, after transfer from 50% seawater to 5% seawater. Plasma sodium concentrations decreased significantly in toadfish in 5% seawater and in one group of eels in fresh water. Plasma levels of cortisol, a major mineralocorticoid in teleosts, and plasma volume, measured in eels, remained relatively constant. There are no clear correlations between plasma renin levels and those of plasma sodium or plasma cortisol. These results provide no evidence that the need of these fishes to conserve sodium when in hypo-osmotic media stimulates the renin–angiotensin system.
EFFECT OF A SKELETON PHOTOPERIOD ON THE DAYLENGTH-DEPENDENT RESPONSE TO OESTROGEN IN CANARIES (SERINUS CANARIUS)
Authors: STEEL ELIZABETH , HINDE R. A. 
Published: December 2008

SUMMARY
Previous studies have shown that ovariectomized canaries, injected with 50 μg oestradiol benzoate thrice weekly, show more oestrogen-induced nest-building on a long day than on a short day. In this study the same effect was obtained with castrated canaries.
The influence of time available for building was assessed first by comparing castrated males on skeleton long days with birds on short days, the total number of light hours being equal. More birds in the skeleton long-day group placed material in the nest, and did so with a shorter latency, than birds in the short-day group. Thus the differences between short- and long-day birds are unlikely to be due entirely to differences in the time available. However, some of the long-day birds were no more active than the short-day ones suggesting that the skeleton long-day schedule does impose some constraint.
In a third experiment photorefractory females (whose ovaries do not secrete oestrogen in response to long days) kept on a long skeleton-day scored similarly on all measures of building as birds kept on a full 14 h day and significantly more than birds on a short day.
The results also indicate that the birds are measuring daylength by means of a diurnal rhythm of photosensitivity, an effect comparable to that of longer photoperiods on gonadal growth.
ADVANCEMENT OF OVULATION IN THE GUINEA-PIG WITH EXOGENOUS PROGESTERONE AND RELATED EFFECTS ON LENGTH OF THE OESTROUS CYCLE AND LIFE SPAN OF THE CORPUS LUTEUM
Authors: JOSLYN W. D. , WALLEN K. , GOY R. W. 
Published: December 2008

SUMMARY
A single subcutaneous injection of progesterone (0·4 mg) was given to intact female guinea-pigs on either day 1, 7, 12, 13, 14, 15, or 16 of the behavioural oestrous cycle (day of oestrus is day 0). Injections given on either day 1 or day 7 had little effect, although there was a suggestion that injection on day 7 produced a lengthening of the cycle. Animals injected on either day 12 or day 13 underwent cycles of 16·9 and 18·1 days average length, respectively, which were significantly longer than the mean of 15·8 days for uninjected control females.
Injection of progesterone on days 14, 15, or 16 was associated with one of three distinct sequelae: (1) simple prolongation of the cycle associated with a return to spontaneous oestrus 4–7 days later; (2) advancement of ovulation, formation of abnormal corpora lutea, and return to spontaneous oestrus 9–13 days later, and (3) return to spontaneous oestrus 14–16 days after the progesterone injection. These findings suggest that progesterone can cause the release of ovulatory amounts of gonadotrophin following a period of endogenous oestrogen conditioning of the gonadotrophic system. If progesterone is administered before oestrogen conditioning is complete, then it inhibits or delays the conditioning process, and spontaneous oestrus and ovulation are postponed.
PRODUCTION OF ANTISERA AGAINST HIGHLY PURIFIED HUMAN FOLLICLE-STIMULATING HORMONE, LUTEINIZING HORMONE AND THYROID-STIMULATING HORMONE
Authors: THORELL J. I. , HOLMSTRÖM B. 
Published: December 2008

SUMMARY
Antisera were produced in rabbits against highly purified preparations of human LH (2000 or 10000 i.u./mg), human FSH (5500 i.u./mg), and human TSH (7·5 i.u./mg). Most rabbits produced antisera of high titre and high avidity. Cross-reactions were minimal between human TSH and human chorionic gonadotrophin (HCG) and between human FSH and HCG but marked between human LH and HCG. TSH and FSH also showed a constant but relatively weak cross-reaction. LH cross-reacted with FSH to a higher degree than did HCG. The avidity of the antisera was high. It was concluded that much of the lack of specificity recorded for glycoprotein antisera are effects of impure immunogens. Some of the true cross-reactions are probably explained by shared antigenic determinants of the β-subunits. Unadsorbed antisera could be used for assay of FSH and TSH in plasma from pregnant women.
IMMUNOREACTIVE LUTEINIZING HORMONE RELEASING FACTOR IN PITUITARY STALK BLOOD FROM FEMALE RATS: SEX STEROID MODULATION OF RESPONSE TO ELECTRICAL STIMULATION OF PREOPTIC AREA OR MEDIAN EMINENCE
Authors: SHERWOOD NANCY M. , CHIAPPA SHARON A. , FINK G. 
Published: December 2008

SUMMARY
The effects of sex steroid hormones on the responsiveness of the neural mechanism responsible for the secretion of LH-RF have been examined in the female rat. Responsiveness was determined at pro-oestrus by measuring the increments in immunoreactive LH-RF of pituitary stalk blood produced by electrical stimulation of the medial preoptic area or median eminence. Ovariectomy on the morning of dioestrus reduced the LH-RF response to preoptic stimulation while oestradiol benzoate (OB) or testosterone propionate (TP) administered immediately after ovariectomy significantly augmented the response. The facilitatory effect of TP was possibly due to its conversion to an aromatized derivative since 5α-dihydrotestosterone monobenzoate was ineffective. Progesterone did not facilitate preoptic responsiveness, and, when administered to animals ovariectomized at 12.00 h of pro-oestrus, reduced the LH-RF response at 18.00 h the same day. Stimulation of the median eminence produced a significantly greater increment in LH-RF than stimulation of the preoptic area. The facilitatory action of OB on the LH-RF response was less marked for median eminence compared with preoptic stimulation. The administration of ICI 46474 at 17.00 h of dioestrus did not reduce preoptic responsiveness on the morning of the next day, suggesting that this compound does not act as an 'antioestrogen' at the level of the preoptic area.
PROSTATIC DISTRIBUTION OF SEX HORMONE-BINDING GLOBULIN AND CORTISOL-BINDING GLOBULIN IN BENIGN HYPERPLASIA
Authors: COWAN R. A. , COWAN SHEILA K. , GILES C. A. , GRANT J. K. 
Published: December 2008

SUMMARY
Sex hormone-binding globulin-(SHBG) and cortisol-binding globulin-(CBG) like proteins have been demonstrated in prostatic tissue surgically removed from patients with benign prostatic hyperplasia. These proteins are not easily removed by superfusion of tissue slices. Epithelial tissue was separated from stroma and found not to contain the SHBG- or CBG-like proteins. Substantial amounts of these proteins, however, remained associated with the stroma. It is suggested that they may be constituents of interstitial fluid in this tissue compartment. The possible significance of this in benign prostatic hyperplasia is discussed.
PARATHYROID HORMONE AND EGGSHELL CALCIFICATION IN JAPANESE QUAIL
Authors: DACKE C. G. 
Published: December 2008

SUMMARY
The effect of parathyroid hormone (PTH) on egg-shell calcification has been investigated in egg-laying Japanese quail. Lilly parathyroid extract (PTE) when injected into quail within 2–6 h of oviposition caused a significantly increased deposition of a chronic 45Ca label into the sequential egg-shell compared with the previous egg in the clutch, indicating increased mobilization of bone Ca and its subsequent incorporation into the egg-shell. At the same time egg-shell weight/unit area and egg-shell Ca/unit area were significantly decreased. Parathyroid extract injected 12–16 h after oviposition had none of these effects. Purified PTH also caused a significant decrease in egg-shell weight/unit area if injected within 2–6 h of oviposition. This result indicated an action of PTH either directly or indirectly on the avian oviduct limiting egg-shell calcification. The loss of responses in the 12–16 h treated birds may reflect high endogenous PTH levels with subsequent saturation of target organ receptors.
DIURNAL VARIATION AND THE EPISODIC RELEASE OF PLASMA GONADOTROPHINS IN JAPANESE QUAIL DURING A PHOTOPERIODICALLY INDUCED GONADAL CYCLE
Authors: GLEDHILL B. , FOLLETT B. K. 
Published: December 2008

SUMMARY
Blood samples were taken every 3 h, over a 27 h period, from (1) a group of 12 intact male quail on short days (lights on 09.00–17.00 h) and during the 2nd, 15th and 36th day of photostimulation (lights on 09.00–05.00 h); (2) 12 castrated male quail on the 2nd, 20th and 43rd long day, and (3) 12 intact male quail on the 12th long day. Plasma LH was measured in all samples and FSH in the 43rd long day castrate and 12th long day intact male samples. Although there was considerable variation in the levels of LH and FSH, both between birds and between samples taken from the same bird, statistical analyses failed to reveal any diurnal (or circadian) rhythm at any time. There was a marked correlation between the LH and FSH levels in all samples.
Possible episodic LH secretion was investigated by taking blood samples every 15 min for between 3 and 6 h from six intact male quail and six laying females on long days. Samples were obtained from each bird at three time-periods which were arranged so as to overlap and cover the first 12 h of the daily photoperiod. Statistical analysis suggested that episodes of secretion occurred 6–10 times/day in males, and 4–8 times/day in females. The pulses appeared to occur at random.
EFFECT OF α-MELANOCYTE-STIMULATING HORMONE AND TESTOSTERONE ON CUTANEOUS AND MODIFIED SEBACEOUS GLANDS IN THE RAT
Authors: THODY A. J. , COOPER MARY F. , BOWDEN P. E. , MEDDIS D. , SHUSTER S. 
Published: December 2008

SUMMARY
The effects of α-MSH and testosterone propionate on sebum secretion, sebaceous gland volume, dermal lipogenesis, and preputial gland weight and lipogenesis were examined in hypophysectomized rats. Hypophysectomy reduced sebum secretion, sebaceous and preputial gland size, and dermal and preputial gland lipogenesis. The greatest effects were seen on the biosynthesis of wax esters and squalene. Testosterone propionate (TP) increased sebum secretion, sebaceous gland volume and preputial gland weight and lipogenic activity, but had no significant effect on the pattern of lipid labelling. α-MSH had no effect on sebaceous or preputial gland size, but increased sebum secretion and dermal lipogenesis, especially wax ester biosynthesis. When given together TP and α-MSH had a synergistic effect on sebum secretion and on dermal and preputial gland lipogenesis, and the pattern of lipid labelling was shifted towards normal. TP and α-MSH also showed synergism in increasing preputial gland weight, but together they had no greater effect on sebaceous gland volume than that achieved with TP alone.
These results suggest that TP and α-MSH have different actions on the sebaceous glands with α-MSH acting predominantly on lipogenesis and TP on cellular proliferation and turnover leading to an increase in gland size. Preputial glands differ from cutaneous sebaceous glands in their response to α-MSH and androgen which could be a reflection of their more specialized function.
CHANGES IN BRAIN, PITUITARY AND UTERINE CYTOPLASMIC OESTROGEN RECEPTORS INDUCED BY OESTRADIOL-17β IN THE OVARIECTOMIZED RAT
Authors: MORRIS I. D. 
Published: December 2008

SUMMARY
The oestrogen specific, high-affinity cytosol receptor (HAR) from amygdala, anterior, middle and posterior hypothalamus, pituitary and uterus was studied in the ovariectomized rat. A single in-vivo injection of oestradiol-17β produced significant changes in both the tissue HAR concentrations and the apparent dissociation constants (Kd) determined in vitro. Four hours after oestradiol-17β treatment (20 μg/kg), the HAR concentration was depleted in all tissues except the posterior hypothalamus. A lower dose of oestradiol-17β (4 μg/kg) produced similar changes in HAR concentration with the exception of those in the amygdala and posterior hypothalamus. Twenty-four hours after oestradiol-17β, HAR concentrations had returned to pre-injection levels in all tissues except the uterus. The uterine HAR concentrations were raised after both doses of oestradiol-17β. The apparent tissue cytosol Kd values were decreased by both doses of oestradiol-17β. The results suggest that brain, pituitary and uterine oestrogen cytosol HARs react to plasma oestrogen in a manner predictable by the steroid receptor hypothesis. The oestradiol-17β-induced differential effects upon the tissue cytosol concentration may contribute to the overall spectrum of action of oestrogen in the central and peripheral reproductive processes.
EFFECT OF ADRENERGIC BLOCKADE AND DEXAMETHASONE ON THE ALDOSTERONE RESPONSE TO BRAIN STIMULATION IN THE RHESUS MONKEY
Authors: JENKINS J. S. , FRANKEL R. J. , WRIGHT J. J. , KHAN M. U. A. 
Published: December 2008

SUMMARY
The increase in aldosterone and plasma renin activity (PRA) observed after stimulation of extrahypothalamic sites within the brain of the rhesus monkey was prevented by the prior administration of the β-adrenergic blocking agent propranolol. α-Adrenergic blockade by phentolamine had no inhibiting effect. Propranolol only partially reduced the response of aldosterone to lateral hypothalamic stimulation in spite of inhibition of PRA; a partial reduction in aldosterone was also obtained from this site after dexamethasone treatment without any effect on PRA. It was concluded that the increase in aldosterone observed after extra-hypothalamic stimulation was mediated mainly through the renin-angiotensin mechanism whereas in the case of the hypothalamus, release of ACTH was also a contributory factor.
ONSET OF OESTROGEN-INDUCED PROLACTIN SECRETION AND DNA SYNTHESIS BY THE RAT PITUITARY GLAND
Authors: JACOBI JOAN , LLOYD H. M. , MEARES J. D. 
Published: December 2008

SUMMARY
The times of onset of oestrogen-induced prolactin secretion and DNA synthesis were studied in the pituitary gland of the male rat. At intervals from 3 to 96 h after injection of 10 mg diethylstilboestrol dipropionate, serum and pituitary prolactin concentrations were measured by radioimmunoassay and pituitary DNA synthesis by incorporation of [3H]thymidine in vitro. Serum prolactin was raised significantly from 6 h onwards and DNA synthesis was increased from 30 h onwards. Pituitary prolactin concentration began to increase at 30 h. Significant correlations were obtained between serum prolactin and DNA synthesis from 24 to 72 h but not during the period of prolactin secretion from 6 to 24 h.
HORMONAL EFFECTS ON CANINE PROSTATIC EXPLANTS IN ORGAN CULTURE
Authors: SINOWATZ F. , PIERREPOINT C. G. 
Published: December 2008

SUMMARY
Explants of canine prostate were cultured in a defined medium for periods of up to 5 days with and without added steroids. Testosterone and 5α-dihydrotestosterone failed to maintain their histological integrity and induced a greatly increased formation of stromal elements. Epitestosterone and 5α-dihydroepitestosterone were partially successful in maintaining epithelial height although secretory activity was not preserved. The only steroid that sustained epithelial height and secretory activity whilst keeping stromal growth at a minimum was 5α-androstane-3α, 17α-diol. The three other epimeric androstanediols were ineffective.
LIGHT AND ELECTRON MICROSCOPIC STUDIES OF THYROTROPHIN RELEASING HORMONE-INDUCED GROWTH HORMONE AND PROLACTIN RELEASE IN HYPOPHYSECTOMIZED RATS BEARING AN ECTOPIC PITUITARY GLAND
Authors: ROSSI G. L. , PROBST DOROTHEA , PANERAI A. E. , GIL-AD IRIT , COCCHI DANIELA , MÜLLER E. E. 
Published: December 2008

SUMMARY
A light microscopic and ultrastructural study of anterior pituitary glands transplanted under the kidney capsule of hypophysectomized rats was performed, in basal conditions and after stimulation with thyrotrophin releasing hormone, at various intervals (24 h–2 months) after transplantation. Confirming previous biochemical findings, the results suggest that with time, somatotrophs acquire sensitivity to thyrotrophin releasing hormone and respond with increased exocytosis at doses that were found ineffective in pituitary glands in situ. Thryotrophin releasing hormone stimulation did not seem to influence the morphology of prolactin cells, which were already highly active under basal conditions at all time intervals.
EVIDENCE FOR DOPAMINERGIC CONTROL OF THYROTROPHIN SECRETION IN THE RAT
Authors: RANTA TAPIO , MÄNNISTÖ PEKKA , TUOMISTO JOUKO 
Published: December 2008

SUMMARY
The effects of two dopamine agonists (apomorphine and bromocriptine) and a dopamine antagonist (pimozide) on cold- or thyrotrophin releasing hormone (TRH)-induced TSH secretion were studied in normal male rats. Apomorphine given in various doses (0·5–10 mg/kg body wt) 10 min before exposure to cold significantly depressed TSH secretion. Large doses of bromocriptine (5–10 mg/kg body wt) given 1 h before exposure to cold, also blocked this response whereas a smaller dose (2·5 mg/kg body wt) given 30 min, 1, 3 or 6 h before cold exposure or repeated doses (0·1–2·5 mg/kg body wt) for 3 days did not modify cold-induced TSH secretion. Pimozide given in various doses (0·25–2·5 mg/kg body wt) 1 h before exposure to cold did not alter the cold response, but 2·5 mg/kg reversed the inhibition caused by apomorphine or bromocriptine. None of these drugs affected TRH-induced TSH secretion. These results suggest that there are no dopaminergic receptors on the pituitary thyrotrophs, but that dopamine might be an inhibitory transmitter in the brain involved in the regulation of TSH secretion in the rat.
THE HYPOTHALAMIC CENTRES INVOLVED IN THE CONTROL OF PRODUCTION AND RELEASE OF PROLACTIN IN SHEEP
Authors: WOLIŃSKA EWA , POLKOWSKA JOLANTA , DOMAŃSKI E. 
Published: December 2008

SUMMARY
Lesions made in the anterior medial basal hypothalamus (MBH) in pregnant or lactating ewes caused lack of development of the mammary gland and depressed milk yield, a decrease in plasma prolactin concentration and structural changes in the prolactin cells as manifested by a lack of the expected degranulation (lack of the hormone release) or by atrophic changes and diminished cell granulation (or granule synthesis). Lesions made in the caudal MBH during pregnancy advanced development of the mammary gland, induced a rapid increase in the plasma prolactin concentration and caused extensive degranulation of prolactin cells. These results indicate that at least two functional systems controlling the secretion and production of prolactin exist in the hypothalamus of sheep: an anterior system which is stimulatory and a caudal which is inhibitory.
PROSTAGLANDIN A2 AT LOW RATES OF INFUSION RESTORES THE ANTIDIURETIC EFFECT OF VASOPRESSIN IN LITHIUM-TREATED RATS
Authors: MTABAJI J. P. , ROBINSON C. J. , MANKU M. S. , CRONIN D. , HORROBIN D. F. 
Published: December 2008

SUMMARY
To test the effect of prostaglandin A2 (PGA2) on renal function, infusions of PGA2 (0·7 ng/ kg/min), arginine-vasopressin (AVP) (1·25 ng/kg/min) and PGA2 plus AVP were administered to male rats made resistant to the antidiuretic effect of AVP by pre-treatment with lithium. In non-lithium-treated control rats, AVP had its expected antidiuretic action but in lithium-treated rats neither urinary volume nor osmolarity was changed. Prostaglandin A2 alone had no effect on urine output in lithium-treated rats; AVP plus PGA2 infused together evoked a near normal antidiuretic response. This antidiuretic action of PGA2 contrasts with the diuretic action reported by others. However, our infusion rates were 300–4000 times lower than those of other workers and it is suggested that PGs may have opposite actions on the kidney depending on their concentration.
The effect of indomethacin (a blocker of prostaglandin synthesis) on urine flow was tested in five groups of rats on different régimes of liquid intake. Urine flow was reduced in the three groups with the highest urine volumes before treatment, and increased in the two groups with the lowest urinary volumes, again indicating that PGs may have both diuretic and antidiuretic actions.
EFFECTS OF LUTEINIZING HORMONE RELEASING HORMONE ON PLASMA FOLLICLE-STIMULATING HORMONE AND LUTEINIZING HORMONE LEVELS IN THE FERRET
Authors: DONOVAN B. T. , TER HAAR M. B. 
Published: December 2008

SUMMARY
Heterologous radioimmunoassays for FSH and LH were employed to examine the effect of synthetic LH-RH upon gonadotrophin secretion in the ferret. Intravenous injection of 4 μg LH-RH induced a surge of FSH and of LH secretion in male and in female animals. In intact and in castrated males, the rise of LH was much more marked than that of FSH. The gonadotrophin response to LH-RH was greater in anoestrous than in oestrous females; FSH secretion was not enhanced during oestrus. Ovariectomized females behaved as anoestrous females with respect to LH secretion, while FSH secretion remained unchanged. Treatment of ovariectomized females with progesterone did not alter the pattern of response to LH-RH, but oestradiol treatment depressed the reaction to match that seen in oestrous females. Repetitive injections of LH-RH induced repetitive surges of FSH and LH in anoestrous females, but only of LH during oestrus: slow i.v. infusion of LH-RH induced a sustained elevation of plasma LH levels both in oestrous and in anoestrous females; again FSH levels rose only in anoestrous females. Injection of synthetic TRH did not alter gonadotrophin secretion in corresponding groups of male or female ferrets.