bluuebunny/crossref_metadata_2025_split huggingface dataset:
ANOMALOUS EFFECTS OF PROGESTERONE ON THE MATURATION AND SURVIVAL OF SPERMATOZOA IN THE EPIDIDYMIS OF THE GOLDEN HAMSTER
Authors: LUBICZ-NAWROCKI C. M. 
Published: December 2008

SUMMARY
The effect of progesterone on the maturation and viability of epididymal spermatozoa was tested in golden hamsters. The corpus epididymidis and ductus deferens were unilaterally ligated so that mature spermatozoa were isolated in the left cauda epididymidis whilst the contralateral epididymis was left intact. Fertility trials showed that after eight daily consecutive injections of progesterone (1·0 mg) spermatozoa on both sides retained normal fertilizing ability. Treatment with progesterone (0·25 and 1·0 mg) for 12 days, however, decreased the fertilization rate of retained spermatozoa to 44·4% and 0%, respectively, whereas fertilizing ability of spermatozoa from the intact cauda epididymidis remained unimpaired. In addition, progesterone (1·0 mg/day) did not influence passage of spermatozoa through the epididymis. Male hamsters treated with progesterone (0·25 mg/day) in combination with testosterone, 5α-dihydrotestosterone (5α-DHT) or 3α-androstanediol (all at 50 μg/day for 12 days revealed that 3α-androstanediol and 5α-DHT (but not testosterone) antagonized the antifertility effect of progesterone on retained epididymal spermatozoa. Furthermore, treatment of castrated hamsters with testosterone, 5α-DHT or 3α-androstanediol (100, 75 and 12·5 μg/day, respectively) in combination with progesterone (1·0 mg/day) showed that progesterone inhibited the stimulatory effect of testosterone but not that of 5α-DHT and 3α-androstanediol. The dissimilar effect of progesterone on fertilizing ability of spermatozoa in ligated and intact epididymides is discussed.
BIOSYNTHESIS OF ADRENOCORTICAL STEROIDS BY MONOTREMES: ECHIDNA (TACHYGLOSSUS ACULEATUS) AND PLATYPUS (ORNITHORHYNCHUS ANATINUS)
Authors: WEISS MAGDA 
Published: December 2008

SUMMARY
The formation of corticosteroids from [14C]pregnenolone or [14C]progesterone by platypus and echidna adrenal homogenates was studied. Corticosteroids were assayed in the peripheral blood plasma of the platypus. In the platypus nine labelled conversion products were identified. The combined yields of cortisol and cortisone averaged 70% and the combined yields of corticosterone and 11-dehydrocorticosterone averaged 14%. Aldosterone was identified in each experiment in yields below 0·1%. In the echidna ten labelled conversion products were identified. Those in highest yield were 11-deoxycorticosterone and 11-deoxycortisol which contained, respectively, an average of 35 and 11% of the added substrate. The yield of corticosterone was always less than 1% and that of cortisol was consistently lower. Aldosterone was identified in all cases in yields below 0·05%.
The yields of total 11β-hydroxylated conversion products from platypus adrenal exceeded 80%, whereas they were below 1% from glands of male echidnas and 7% from female echidna.
The yield—time curves for labelled conversion products from [14C]-pregnenolone indicated that the biosynthetic pathways of corticosteroid production by the monotreme adrenal are similar to those in eutherian mammals.
From stored endogenous precursors of a platypus adrenal incubated for 30 min, corticosteroids were formed in the following amounts (per 100 mg adrenal): cortisone, 5·1 μg; cortisol, 1·3 μg; 11-dehydrocorticosterone, 1·5 μg. In the peripheral plasma of platypus the concentration of combined cortisol and cortisone was 14 μg/100ml and the combined corticosterone and 11-dehydrocorticosterone was 1·8 μg. The mean ratio of adrenal weight (mg) to body weight (kg) was 39·5 in the echidna and 257 in the platypus. The marked contrast in adrenocortical biosynthetic capacity of the two monotremes is discussed and a comparison of the results is made in relation to higher mammals.
A QUANTITATIVE STUDY OF GENETIC DIFFERENCES IN THE INCIDENCE OF OESTRUS, OVULATION AND PLASMA LUTEINIZING HORMONE CONCENTRATION IN THE SHEEP
Authors: LAND R. B. , PELLETIER J. , THIMONIER J. , MAULÉON P. 
Published: December 2008

SUMMARY
Seasonal variation in the ovulation rate and incidence of ovulation was examined in 15 Romanov and 15 Solognote ewes by endoscopy. The ovulation rate of the Romanovs was found to be related to the incidence of ovulation (r = 0·78) and to the incidence of oestrus as measured by daily teasing with aproned entire rams (r = 0·83). The ovulation rate of the Romanovs was greater than that of the Solognotes, and was 2·6 and 1·1 corpora lutea in the two breeds, respectively, in the autumn. The durations of the breeding season and of oestrus of the Romanovs exceeded those of the Solognotes.
The characteristics of the preovulatory discharge of luteinizing hormone (LH) and the daily plasma LH levels were studied by radioimmunoassay in the Romanov and Solognote ewes and in ewes of the Berrichon and Berrichon × Romanov breeds. The interval between the onset of oestrus and the discharge of LH was greater in the Romanovs (17·6 h) than in the other breeds (mean = 7·5 h). The total release of LH, however, was not related to the number of corpora lutea formed.
THE EFFECTS OF SYNTHETIC GONADOTROPHIN RELEASING FACTOR ON THE RELEASE OF LUTEINIZING HORMONE AND FOLLICLE-STIMULATING HORMONE FROM OVINE PITUITARY TISSUE IN VITRO
Authors: CRIGHTON D. B. 
Published: December 2008

SUMMARY
A synthetic decapeptide gonadotrophin releasing factor was tested for effects on the release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) using an ovine pituitary incubation system. The effects of other synthetic peptides used at similar doses were studied.
The synthetic decapeptide consistently provoked significant increases in the LH content of the incubation medium at doses equal to or in excess of 0·5 ng/flask (0·2 ng/ml medium). Significant increases in the FSH content of the incubation medium at doses equal to or in excess of 0·25 ng/flask (0·1 ng/ml medium) were observed. The other synthetic peptides failed to influence LH or FSH release in vitro even at a dose 20–40 times greater.
The results demonstrate that the decapeptide releases both LH and FSH from sheep pituitary tissue, suggesting that it may play a role in the release of both hormones in vivo in the sheep.
ANALYSIS OF THE ZINC-BINDING PROTEIN DERIVED FROM THE HUMAN BENIGN HYPERTROPHIC PROSTATE
Authors: HEATHCOTE J. G. , WASHINGTON R. J. 
Published: December 2008

SUMMARY
Preliminary analysis of the zinc-binding protein isolated from the human benign hypertrophic prostate gland was carried out using a micro method. The most interesting feature of the amino acid composition of the protein hydrolysate appears to be the large molar proportion of histidine which is present. This might account for the binding of divalent cations.
ROLE OF THE ADRENAL CORTEX IN THE ADAPTATION OF THE MONOTREME TACHYGLOSSUS ACULEATUS TO LOW ENVIRONMENTAL TEMPERATURE
Authors: AUGEE M. L. , McDONALD I. R. 
Published: December 2008

SUMMARY
When exposed to a low ambient temperature of 5 °C, adrenalectomized echidnas were able to increase their metabolic rate and to maintain their body temperature within the normal range for no more than 48 h — less than 12 h in five out of six animals. Thereafter, activity, metabolic rate, cardiac rate and body temperature declined and the animals became torpid.
When maintained with daily i.m. injections of 1–2 mg cortisol acetate/kg, adrenalectomized echidnas maintained activity and normal body temperature in the cold environment indefinitely. When cortisol injections were withheld and exposure to cold continued, normal body temperature was maintained for a further 10 days, after which it declined rapidly.
The onset of torpor was always preceded by a marked fall in plasma glucose concentration, as occurred in normal, but fasted, echidnas after prolonged exposure to cold. Both cortisol and corticosterone have glucocorticoid activity in echidnas, and torpor was prevented in adrenalectomized echidnas by preventing the fall in plasma glucose with either intermittent injections or constant rate infusions of glucose solutions.
The adrenal glands of normal echidnas exposed repeatedly to low environmental temperatures showed marked hypertrophy and increase in lipid content.
It is concluded that adrenocortical secretions are necessary for the metabolic response to cold stress in these prototherian mammals, and a major role of the corticosteroids is in maintenance of normal blood glucose concentrations, presumably by enhancing hepatic gluconeogenesis.
PROPERTIES OF A SIMPLIFIED BIOASSAY FOR ADRENOCORTICOTROPHIC ACTIVITY USING THE STEROIDOGENIC RESPONSE OF ISOLATED ADRENAL CELLS
Authors: LOWRY P. J. , McMARTIN C. , PETERS JUDY 
Published: December 2008

SUMMARY
A reproducible method for isolating intact cells from the adrenal glands of a small number of rats (four to six) is described. The incubation conditions and fluorometric corticosteroid assay were modified to enable a large number of incubations to be carried out with each batch of cells. Linear regression analysis of log-dose—response curves for adrenocorticotrophin (ACTH) analogues yields potency ratios with 95% confidence limits which are usually less than ± 20%. The ED50 of the assay is about 50 pg/ml for natural ACTH and 7 pg/ml for corticotrophin-(1–24)-tetracosapeptide. Insulin and prostaglandin E2 had no effect on the steroidogenic response to ACTH while cyclic AMP at high doses was steroidogenic but gave a much steeper log-dose—response curve than ACTH. α- and β-melanocytestimulating hormone (MSH) were both agonists but only at concentrations 1 × 106 times higher than those of ACTH. Cells isolated from rabbit adrenals were similar to those from the rat in their responsiveness to ACTH but were unresponsive to amounts of MSH sufficient to stimulate rat adrenal cells.
SOME PROPERTIES OF THE HYDRO-OSMOTIC VASOPRESSIN 'EFFECTOR': INTERACTIONS WITH N-ETHYLMALEIMIDE
Authors: BENTLEY P. J. 
Published: December 2008

SUMMARY
N-Ethylmaleimide (NEM) prevents the hydro-osmotic response to vasopressin. It has no significant effects on osmotic water movement in the absence of the hormone. The hydro-osmotic effects of cyclic AMP and hyperosmotic mannitol solutions are also reduced by NEM.
After exposure to vasopressin, cyclic AMP, or hyperosmotic mannitol, the osmotic permeability declines to the preincubation level but after exposure to NEM this was prevented. This effect was seen after exposure to 10−4 and 10−5 m-NEM, i.e. concentrations that do not alter the onset of the response.
The increased osmotic permeability after treatment with NEM is not due to a non-specific effect caused by a 'fixation' of the tissue in a distorted condition (such as occurs during rapid water transfer) since it was seen even after treatment of the tissue under conditions when no osmotic water movement was occurring, that is with iso-osmotic Ringer solution on both sides.
The effect of NEM could not be mimicked by exposure of the bladder to 20 mm-Ca2+, 0·1 mm-Zn2+ or 1 mm-l-cysteine.
THE EPISODIC NATURE OF CHANGES IN OVINE PLASMA CORTISOL LEVELS AND THEIR RESPONSE TO ADRENALINE DURING ADAPTATION TO A NEW ENVIRONMENT
Authors: McNATTY K. P. , THURLEY D. C. 
Published: December 2008

SUMMARY
Large and rapid variations were found in the plasma cortisol levels of housed and cannulated sheep. Adrenaline injected i.v. caused increased plasma levels of cortisol that were proportionate to the dose. This response of cortisol to adrenaline was larger when sheep were newly housed, than when the sheep had been housed and sampled for 2 weeks. Response to adrenocorticotrophin also diminished over 2 weeks. Dexamethasone abolished the response to adrenaline. Tyrosine and DOPA had little effect on cortisol levels, dopamine and noradrenaline had some effect, but none had as great an effect as adrenaline.
METABOLISM OF RNA AND PYRIMIDINE NUCLEOTIDES IN THE UTERUS DURING THE EARLY DECIDUAL CELL REACTION
Authors: MILLER B. G. 
Published: December 2008

SUMMARY
Changes in the metabolism of pyrimidine 5′-nucleotides and RNA in the mouse uterus during the oil-induced decidual cell reaction were investigated. During the first 20 h after the intraluminal injection of 10 μl sesame oil the amounts of HClO4-soluble nucleotides and uridine 5′-nucleotides in the treated horn increased by 55% and 115%, respectively. During the same interval RNA increased by 101%, while the increase in protein was much smaller, and the amount of DNA remained almost unchanged.
Doses of [2-14C]uridine, [5-3H]cytidine and [5-3H]orotic acid were administered to mice 20 min before killing. After [2-14C]uridine injection the specific activity of the uridine 5′-nucleotide fraction 20 h after the oil stimulus had not changed, while the specific activity of RNA increased by 43% during the 20-h interval. Similar results were obtained when [5-3H]-cytidine was injected. In contrast, after an injection of [5-3H]orotic acid the specific activities of both the uridine 5′-nucleotide and RNA fractions decreased with increasing time after the intraluminal injection of oil. When approximate rates of RNA synthesis were calculated independently from the data for [2-14C]uridine and [5-3H]orotic acid incorporation in these two fractions, the results agreed well, and indicated that the rate of synthesis of RNA in the decidualizing uterus increased by 64% and 163% at 8 and 20 h respectively after the intraluminal administration of sesame oil.
INFLUENCE OF THE ADRENAL GLAND ON PROSTATIC ACTIVITY IN ADULT RATS
Authors: MOBBS B. G. , JOHNSON I. E. , CONNOLLY J. G. 
Published: December 2008

SUMMARY
The weight of the accessory sex glands, and the citrate and nucleic acid content of the ventral prostate (VP) glands, were examined in animals which had been adrenalectomized 30 days previously and in intact control rats. Adrenalectomy greatly reduced the citrate content, but did not affect the nucleic acid content of the VP. It was concluded that the adrenals stimulated prostatic function rather than growth.
The concentration of radioactivity in the accessory sex glands of adrenalectomized and/or castrated animals after the injection of [3H]testosterone was compared with that in sham-operated controls. Radioactivity was related to the DNA content of the VP of the four groups. It was concluded that adrenalectomy facilitated the uptake and/or retention of androgen.
[3H]Corticosterone was not retained by any of the accessory sex glands of animals adrenalectomized and castrated 2 days previously. It seems unlikely that the glands should be considered 'target organs' for corticosterone in the accepted sense of the term, but it is suggested that corticosteroids may help to maintain the balance between differentiation and growth in the VP by influencing the metabolism of androgens by the prostate gland.
MASCULINIZING EFFECTS OF A TESTICULAR INTERSTITIAL CELL TUMOUR GRAFT ON FEMALE RATS
Authors: POURREAU-SCHNEIDER NATALIE 
Published: December 2008

SUMMARY
An androgen-producing testicular interstitial cell tumour of rats was grafted into intact and spayed female rats. The tumour inhibited luteinization, produced follicular atresia, stimulated the uterine myometrium and endometrium, and caused vaginal mucus formation. Anoestrus set in and mating behaviour disappeared, rendering gestation impossible. After surgical removal of the tumour, the masculinization disappeared rapidly. With the return of vaginal oestrus (sometimes only 4 days after removal of the tumour) most of the rats mated and gave birth to normal young. When a palpable nodule reappeared, the reproductive function was again lost. The tumour produced similar changes in the target organs of spayed females. The inhibitory action of the endocrine tumour on pituitary gonadotrophic hormone production was shown by the absence of castration cells in the pituitary of the tumour-bearing spayed female.
THE EFFECT OF STILBOESTROL ANALOGUES ON THE METABOLISM OF STEROIDS BY THE TESTIS AND PROSTATE OF THE RAT IN VITRO
Authors: DANUTRA VARAPAN , HARPER MAUREEN E. , GRIFFITHS K. 
Published: December 2008

SUMMARY
Male Sprague—Dawley rats were injected (i.m.) daily for 10 days with 100 μg of either oestradiol-17β, diethylstilboestrol (DES), dl-dihydrodibutylstilboestrol (dl-DHBS) or meso-dihydrodibutylstilboestrol (meso-DHBS) in 0·2 ml sesame oil. After 10 days, the testicular tissue was removed and incubated simultaneously with [7α-3H]dehydroepiandrosterone and [4-14C]17α-hydroxyprogesterone. Less testosterone was synthesized by the testicular tissue from animals treated with oestradiol-17β, DES and meso-DHBS than by the controls or animals treated with dl-DHBS. The decreased synthetic activity was related to the decreased activity of both the 17β-hydroxysteroid dehydrogenase and 17α-pregnene-C17, 20-lyase enzyme systems.
Prostatic tissue was also incubated with [7α-3H]testosterone. Administration of DES, oestradiol-17β or meso-DHBS increased the metabolism of testosterone by the prostatic tissue with a marked effect on the 5α-reductase enzyme system.
PITUITARY SECRETION OF PROLACTIN, LUTEINIZING HORMONE AND FOLLICLESTIMULATING HORMONE IN ADULT FEMALE RATS TREATED NEONATALLY WITH OESTROGEN
Authors: NAGASAWA HIROSHI , YANAI REIKO , KIKUYAMA SAKAE , MORI JUNICHI 
Published: December 2008

SUMMARY
The serum and pituitary levels of prolactin, luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were determined by radioimmunoassay in adult female rats treated neonatally with oestrogen and were compared with levels in normal cyclic rats at 90, 150 and/or 180 days of age. The serum level of prolactin was significantly higher and its pituitary content and concentration were lower in oestrogenized rats than in control rats at early prooestrus and on the 2nd day of dioestrus. The level of LH in the serum of oestrogenized rats was similar to the level in control rats at pro-oestrus and was higher than that of the controls at dioestrus. Pituitary levels of LH were lower in oestrogenized rats than in control rats at both pro-oestrus and dioestrus. The serum and pituitary levels of FSH in the oestrogenized rats were intermediate between the values found at dioestrus and at pro-oestrus in the controls. The results demonstrate that the pituitary of the neonatally oestrogenized female rat constantly secretes considerable amounts of these hormones.
EFFECTS OF TESTOSTERONE AND FOLLICLE-STIMULATING HORMONE ON SPERMATOGENESIS IN ADULT MICE DURING TREATMENT WITH OESTRADIOL
Authors: DAVIES A. G. , COUROT M. , GRESHAM P. 
Published: December 2008

SUMMARY
Adult male mice were treated with oestradiol for 10 weeks and for the last half of this period they were given relatively large daily doses of testosterone and highly purified human pituitary follicle-stimulating hormone (FSH), singly and in combination.
Oestradiol treatment reduced and testosterone restored the yields of mature (step 16) spermatids from round (step 7) spermatids, round spermatids from pachytene primary spermatocytes and pachytene from preleptotene spermatocytes. At the dose level used FSH was not effective alone but appeared to augment the effect of testosterone on the yield of round spermatids from preleptotene spermatocytes.
EFFECT OF ERGOT ALKALOIDS UPON LUTEAL FUNCTION IN THE FERRET
Authors: BLATCHLEY F. R. , DONOVAN B. T. 
Published: December 2008

SUMMARY
Since ergocornine is believed to block prolactin secretion in several species, the drug was given to pseudopregnant ferrets in an attempt to define the rôle of the hormone in the control of luteal function. The effects of ergocornine, and of the more potent analogue 2-bromo-α-ergocryptine, were followed by assay of the progestin content of the blood and histological examination of the ovaries. Ergocornine was given at the time of induction of pseudo-pregnancy by an injection of luteinizing hormone (day 0), on day 1, days 0 and 1, days 0, 2, 4 and 6, or day 7, and 2-bromo-α-ergocryptine on days 0, 1, 2 and 3, or 7, 8, 9 and 10. A lasting depression of plasma progestin content occurred after the injection of ergocornine on days 0 and 1, perhaps because of interference with the formation of the luteal bodies. Other injection régimes had little effect on progestin secretion.
CENTRAL NERVOUS BLOCKADE OF OESTRADIOL-STIMULATED RELEASE OF LUTEINIZING HORMONE IN THE EWE
Authors: RADFORD H. M. , WALLACE A. L. C. 
Published: December 2008

SUMMARY
The injection of oestradiol benzoate (OB) into the ovariectomized ewe induced a biphasic response in circulating luteinizing hormone (LH). There was a fall in concentration during the first 8–12 h after injection, and then a rapid increase in concentration during the next 12 h. Sodium pentobarbitone anaesthesia, begun either at the time of injection of OB, or 8 or 16 h later, did not affect the first phase, but prevented the second phase of this response. The injection of synthetic luteinizing hormone releasing factor caused a release of LH that was similar both in anaesthetized and conscious ewes. The results indicated a non-nervous site for the inhibitory action of oestrogen on circulating LH, and a central nervous site of action of oestrogen in stimulating LH release.
PITUITARY CONTENT AND PLASMA LEVELS OF GROWTH HORMONE IN FOETAL AND WEANLING RATS
Authors: RIEUTORT M. 
Published: December 2008

SUMMARY
Pituitary and plasma growth hormone were measured in foetal and weanling rats. Growth hormone was first detected in the pituitary (66 ± 8 ng) and plasma (26 ± 2 ng/ml) of 19·5-day-old foetuses. Pituitary growth hormone content increased rapidly up to the end of gestation and after birth. Plasma levels were high after 21·5 days of gestation (147 ± 8 ng/ml) and a further increase was observed at birth. The plasma growth hormone level fell to that of adult levels 5–10 days after birth. An early modulation of growth hormone secretion is discussed since newborn rats aged 2 h showed a rapid decrease in plasma levels at 25 °C while there was no such decrease in newborn animals maintained at 37 °C.
THE EFFECT OF INTRAVENTRICULAR ADMINISTRATION OF 6-HYDROXYDOPAMINE ON PHOTO-INDUCED TESTICULAR GROWTH IN JAPANESE QUAIL
Authors: DAVIES D. T. , FOLLETT B. K. 
Published: December 2008

SUMMARY
The intraventricular infusion into quail of 6-hydroxydopamine, a drug known to cause degeneration of adrenergic neurones, prevented the subsequent photoperiodic stimulation of testicular growth. This effect was seen in about 20% of the treated birds only but in these, the testicular weight and histology as well as the plasma luteinizing hormone (LH) concentration were similar to the same parameters in non-photostimulated birds. 6-Hydroxydopamine inhibited plasma LH significantly within one day of infusion. The results implicate adrenergic pathways in the photoperiodic control of reproduction.
THE HORMONAL INDUCTION OF OVULATION OR OF LUTEINIZATION IN THE INTACT OR HYPOPHYSECTOMIZED GUINEA-PIG
Authors: DONOVAN B. T. , LOCKHART A. N. 
Published: December 2008

SUMMARY
The induction of ovulation and follicular luteinization in the guinea-pig by follicle-stimulating (FSH) and luteinizing (LH) hormones was studied in the intact and in the hypophysectomized animal. Follicular luteinization could be produced as early as day 8 of the oestrous cycle by 250 mu. FSH, but not before day 10 by 400 mu. LH, while either FSH or LH caused ovulation when given on day 12 or later. When injected on day 13, luteinization could be induced with 62·5 mu. FSH or 200 mu. LH. Luteinization of follicles also occurred when 400 mu. LH or 250 mu. FSH was given immediately after hypophysectomy on day 13, but when hormone treatment was delayed for 4·5 h after surgery the incidence of luteinization was greatly reduced. Combined treatment with 200 mu. LH and 125 mu. FSH, by contrast, readily caused luteinization. It is concluded that ovarian follicles are resistant to luteinization during the first half of the oestrous cycle and that the response to LH late in the cycle is dependent upon the maintenance of follicular responsiveness by endogenous gonadotrophin.