bluuebunny/crossref_metadata_2025_split huggingface dataset:
EFFECTS OF DEXAMETHASONE ON THE RESPONSES OF LUTEINIZING HORMONE AND TESTOSTERONE TO TWO INJECTIONS OF LUTEINIZING HORMONE RELEASING HORMONE IN YOUNG POSTPUBERTAL BULLS
Authors: CHANTARAPRATEEP P. , THIBIER M. 
Published: December 2008

Six young postpubertal bulls were studied in two experiments, 3 months apart. In experiment 1, three bulls received i.m. injections of dexamethasone (20 mg) and 5 h later these animals plus three control bulls received i.m. injections of luteinizing hormone releasing hormone (LH-RH, 250 μg). In experiment 2, the controls from experiment 1 received dexamethasone and the treated animals from experiment 1 acted as controls for experiment 2. All bulls also received an i.m. injection of 250 μg LH-RH on day 2 of each experiment. The concentrations of LH and testosterone in samples of jugular blood were determined by radioimmunoassay. There were no significant differences in the patterns of testosterone and LH release between the two experiments. On day 1, the response of LH to LH-RH was significantly (P < 0·05) reduced by dexamethasone, but on day 2 values in the control and treated groups were similar although significantly (P<0·05) lower than values on day 1. The response of testosterone to LH-RH was not affected by dexamethasone.
These results are discussed in terms of the site of action at which dexamethasone may act to depress the release of LH.
EFFECT OF OVARIAN STEROIDS ON PREPUTIAL GLAND ODOURS IN THE FEMALE RAT
Authors: THODY A. J. , DIJKSTRA H. 
Published: December 2008

Sexually experienced male rats were used to test for whole body and preputial gland odours of female rats. The male rats clearly preferred whole body odours of intact female rats to those of preputialectomized female rats. The male rats also preferred the odour of preputial gland tissue of intact female rats to that of ovariectomized female rats and were especially attracted to the preputial gland odours of female rats in pro-oestrus and oestrus. The preputial gland odours of ovariectomized rats that had received oestradiol benzoate for 7 days were attractive to male rats, although similar treatment with progesterone was ineffective. However, a single injection of progesterone given 72 h after a single injection of oestradiol benzoate not only made ovariectomized rats receptive, but also made their preputial gland odours attractive to male rats.
The results suggest that the preputial gland of the female rat is responsible for odours that serve to attract sexually experienced male rats. Ovarian steroids, as well as controlling receptivity in the female rat, would also appear to control the production of sex attractants in the preputial gland. There was no relationship between the size of the preputial glands and their ability to attract male rats which suggests that preputial gland growth and production of sex attractants are not under the same hormonal control.
LEVELS OF ARGININE-VASOPRESSIN AND OXYTOCIN IN THE PITUITARY GLAND AND INDIVIDUAL HYPOTHALAMIC NUCLEI OF THE GENETICALLY OBESE ZUCKER RAT
Authors: CROWLEY W. R. , GEORGE J. M. , JACOBOWITZ D. M. 
Published: December 2008

Laboratory of Clinical Science, National Institute of Mental Health, Bethesda, Maryland 20014, U.S.A. and *Department of Medicine, Ohio State University, College of Medicine, Columbus, Ohio, U.S.A.
(Received 20 September 1977)
The genetically obese Zucker rat exhibits several endocrine disorders, including defects of the female reproductive system such as delayed puberty, irregular oestrous cycles, failure to mate and refractoriness to pseudopregnancy-inducing stimuli (Saiduddin, Bray, York & Swerdloff, 1973). Zucker rats show hyperdipsia, increased plasma osmolality and excrete a large volume of urine with a decreased osmolality and an increased protein content, suggesting a deficiency in the regulation of body fluids (York & Bray, 1971, 1973; Bray, York & Swerdloff, 1973). These considerations, plus the recent findings that in Zucker rats the concentration of noradrenaline is reduced in the hypothalamic paraventricular nucleus and increased in the median eminence (Cruce, Thoa & Jacobowitz, 1976), prompted us to measure levels of arginine-vasopressin (AVP) and
PURIFICATION OF HUMAN PARATHYROID HORMONE: RECENT STUDIES AND FURTHER OBSERVATIONS
Authors: KEUTMANN H. T. , HENDY G. N. , BOEHNERT M. , O'RIORDAN J. L. H. , POTTS J. T. 
Published: December 2008

During the isolation of human parathyroid hormone there is an extensive loss of immunoassayable hormone over the successive extraction steps, due in part to the presence of fragments that are soluble in 4% trichloroacetic acid. These fragments are derived from both the amino- and carboxyl-terminal regions of the hormone.
The hormonal fractions precipitated with trichloroacetic acid were further purified by gel filtration and ion-exchange chromatography. At the final ion-exchange purification step, some preparations of the hormone eluted in multiple fractions. When the various components were characterized separately by immunoassay, amino acid composition, enzymic cleavage and partial sequence analysis, they were found to be closely comparable, although the most acidic fraction contained a blocked terminal amino group.
Extraction of a number of batches of tissue permitted revision of the amino acid composition of human parathyroid hormone. Biosynthetic studies with labelled amino acids confirmed the absence of tyrosine and the presence of phenylalanine and threonine and localized these residues to definite regions of the molecule.
COMPARISON OF FOLLICLE-STIMULATING HORMONE AND LUTEINIZING HORMONE SECRETION AFTER ELECTRICAL STIMULATION OF THE PREOPTIC PART OF THE HYPOTHALAMUS IN FEMALE RATS ANAESTHETIZED WITH ETHYL CARBAMATE OR SODIUM PENTOBARBITONE
Authors: DYER R. G. , TER HAAR M. B. , MAYES LINDA C. 
Published: December 2008

A.R.C. Institute of Animal Physiology, Babraham, Cambridge, CB2 4AT
(Received 17 January 1978)
For over 30 years, the method by which the brain regulates the secretion of gonadotrophic hormones has been studied by electrical stimulation of those parts of the central nervous system thought to be implicated in the control process. Much of the work has been performed on the female rat. In this species, anaesthetic doses of sodium pentobarbitone, administered immediately before the pro-oestrous 'critical period', block the preovulatory surge of luteinizing hormone (LH) for 24 h. The same treatment also reduces the early phase of the pro-oestrous secretion of follicle-stimulating hormone (FSH; Daane & Parlow, 1971). Electrical stimulation of the preoptic part of the hypothalamus can overcome this blocking effect and analysis of the optimum parameters required to restore normal secretion of gonadotrophins may give some insight into the endogenous process (e.g. Everett, 1965; Fink & Aiyer, 1974;
AN IMPROVED METHOD FOR THE SUPERFUSION OF DISPERSED RAT ADRENAL CELLS
Authors: McDOUGALL J. G. , WILLIAMS B. C. 
Published: December 2008

Biophysical Endocrinology Unit, Department of Physics as Applied to Medicine, Middlesex Hospital Medical School, London, W1P 6DB
(Received 6 February 1978)
Steroid secretion by the zona glomerulosa is extremely sensitive to changes in the extracellular concentration of potassium ions ([K+]). The manner in which a change in [K+] is transmitted to the steroidogenic mechanism is not known, but recent data have shown that the flux of 45Ca2+ is altered during such stimulation (Mackie, Warren & Simpson, 1978). More detailed information concerning ion and hormone dynamics during stimulation may be obtained from studies involving the superfusion of dispersed cells.
The 'centrifuge' procedure (Schulster & Jenner, 1975) could not be applied successfully to zona glomerulosa cells; during the first 15 min 50% of the cells were lost, with a subsequent loss of 10% of the original number of cells/h. Thus the alternative 'cell-column' procedure (Lowry & McMartin, 1974) was evaluated and two
INHIBITORY ACTION OF HUMAN FOLLICULAR FLUID ON THE OVARIAN ACCUMULATION OF CYCLIC AMP
Authors: KRAIEM Z. , DRUKER B. , LUNENFELD B. 
Published: December 2008

Institute of Endocrinology, Chaim Sheba Medical Center, Tel Hashomer, Israel
(Received 15 February 1978)
Porcine follicular fluid has been shown to inhibit the gonadotrophin-stimulated accumulation of cyclic AMP in vitro (Ledwitz-Rigby, Gay, Stetson, Young & Channing, 1977). The aim of the present investigation was to test for cyclic AMP inhibitory activity in human follicular fluid obtained during the periovulatory period.
Twelve normal, healthy subjects, aged 21-40 years, with regularovulatorycycles and requiring Iaparotomy for medical reasons, voluntarily consented to participate in the study. Laparotomy was scheduled as close as possible to the expected time of ovulation. With day 0 as the day of the operation, blood samples were taken daily on days −8 to −4 and three times/day on days −3 to 3 and the concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), oestradiol-17β and progesterone in the plasma were determined by radioimmunoassay (Lunenfeld, Insler, Eshkol & Birnboim, 1974). During Iaparotomy,
ANNUAL VARIATIONS IN THE TOTAL LIPID AND PROTEIN CONTENT OF THE LIVER, FAT BODY, OVARY AND PLASMA OF THE FEMALE FROG (RANA ESCULENTA L.)
Authors: MILONE M. , IELA L. , ESPOSITO V. , RASTOGI R. K. , CHIEFFI G. 
Published: December 2008

SUMMARY
The concentrations of lipid and protein in the ovary, fat body, liver and plasma of the female frog (Rana esculenta L.) were found to exhibit marked seasonal variations. There was an interesting correspondence between the depletion of lipid in the plasma and fat body and an increased level of lipid in the ovary. It would appear that oestrogenic steroids stimulate and increase the concentrations of lipids in the plasma, whereas pituitary gonadotrophins influence the uptake of lipids by ovarian tissue for vitellogenesis.
EFFECT OF LUTEINIZING HORMONE ON THE LIPID COMPOSITION OF RAT OVARIES
Authors: SCHULER LINDA A. , FLICKINGER G. L. , STRAUSS J. F. 
Published: December 2008

SUMMARY
The lipid composition of immature rat ovaries was examined after induction of ovulation with pregnant mare serum gonadotrophin and human chorionic gonadotrophin and subsequent (7–8 days later) stimulation with 10 μg LH. Two hours after the administration of LH, there was a decrease of approximately 50% in the concentration of cholesteryl esters in the ovary. The percentages (by weight) of sterol esters containing stearate, linoleate, eicosatrienoate and arachidonate were reduced by LH treatment, whereas the percentage of the C24:4 acid increased. No changes were observed in either the concentrations or fatty acid composition of phospholipids and triglycerides. These observations suggest that the metabolism of cholesteryl esters is acutely affected by LH and that sterol esters bearing long-chain polyunsaturated fatty acids are preferentially mobilized. Liberation of these unsaturated fatty acyl moieties may have significant effects on metabolism in the ovarian cell.
ASSOCIATION BETWEEN 5-HYDROXYTRYPTAMINE RELEASE AND INSULIN SECRETION
Authors: GYLFE ERIK 
Published: December 2008

SUMMARY
The efflux of radioactivity after loading with trace amounts of tritiated 5-hydroxytryptamine ([3H]5-HT) or 5-hydroxytryptophan ([3H]5-HTP) was studied in perifused β-cellrich pancreatic islets from ob/ob mice. Analysis of the effluent revealed that more than 90% of the radioactivity was released as [3H]5-HT after loading with [3H]5-HTP. Increasing the concentration of glucose in the perifusion medium from 3 to 20 mmol/l enhanced the efflux when islets from fed mice were used and this effect was potentiated by the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX). Whereas 20 mm-glucose alone did not stimulate the efflux of 5-HT from islets isolated from mice starved for 3 days, a stimulatory effect was observed in the presence of IBMX. Stimulation of the efflux of radioactivity by glucose was inhibited if calcium was omitted from or adrenaline added to the medium. The results are consistent with the concept of exocytotic release of 5-HT occurring in response to stimulation of insulin secretion, although basal non-exocytotic transport must also be occurring across the β-cell membrane.
EFFECTS OF LOW CALCIUM AND LOW PHOSPHORUS DIETS ON THE DUODENAL ABSORPTION OF CALCIUM IN BETAMETHASONE-TREATED CHICKS
Authors: FOX J. , CARE A. D. , BLAHOS J. 
Published: December 2008

SUMMARY
The effect of oral administration of betamethasone (25 μg kg−1 day−1) on the duodenal absorption of calcium has been studied in chicks using the ligated loop technique in vivo. The chicks were fed normal calcium, normal phosphorus (NCaNP), low calcium, normal phosphorus (LCaNP) or normal calcium, low phosphorus (NCaLP) diets. Daily oral administration of betamethasone for 2–3 weeks markedly reduced the absorption of calcium in chicks fed the NCaNP diet, but did not significantly affect the adaptation in absorption when the NCaLP or LCaNP diets were fed for the same period of time. In one group of chicks, betamethasone was administered daily for 10 days before the birds were transferred to the NCaLP or LCaNP diets. Adaptation was again unaffected by betamethasone treatment. Administration of betamethasone caused a marked retardation in growth-rate, hypercalcaemia and an increased percentage of ash in the tibiae.
FAILURE OF HISTAMINE TO INDUCE THE RELEASE OF LUTEINIZING HORMONE IN CASTRATED RATS PRIMED WITH SEX STEROIDS
Authors: DONOSO A. O. , BANZAN A. M. 
Published: December 2008

Instituto de Investigaciones Cerebrales, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
(Received 10 March 1978)
Injection of histamine into the third ventricle causes the release of luteinizing hormone (LH) in ovariectomized, steroid-primed and pro-oestrous rats (Donoso, Banzan & Borzino, 1976; Donoso, 1978). In oestrous rabbits, intraventricular injection of large doses of histamine or injection of histamine into the mediobasal hypothalamus induces ovulation and secretion of progesterone by the ovaries (Sawyer, 1955; Endröczi & Hilliard, 1965). However, histamine has no effect on the concentration of LH in the plasma of male rats (Donoso & Banzan, 1976). Together, these results suggest that histamine is able to induce the release of LH both before ovulation and in the presence of an adequate hormonal background.
The positive feedback effects of oestradiol and progesterone on the release of gonadotrophins are absent in male rats. Injection of oestradiol, progesterone or testosterone into steroid-primed
SIGNIFICANCE OF PROLACTIN IN SPONTANEOUSLY PERSISTENT OESTROUS RATS
Authors: GOSDEN R. G. 
Published: December 2008

Department of Physiology, University Medical School, Teviot Place, Edinburgh, EH8 9AG
(Received 20 March 1978)
Ageing female rats maintained under standard laboratory lighting conditions (14 h light: 10 h darkness) frequently enter a state of persistent vaginal cornification because the pituitary gland fails to provide an ovulatory surge of gonadotrophic hormones. The ovaries of such animals become dominated by growing and cystic follicles as the corpora lutea disappear. The concentrations of prolactin in the pituitary gland and the circulation during persistent oestrus are known to be raised for at least part of the day (Clemens & Meites, 1971; Mallampati & Johnson, 1974; Shaar, Euker, Riegle & Meites, 1975; J. E. Beach, R. G. Gosden & J. W. Everett, unpublished observations). A possible antigonadotrophic role of prolactin in the aetiology of the persistent oestrous condition should be considered because of the known inverse relationship between the release of prolactin and gonadotrophins
EVIDENCE FOR PLEIOMORPHISM OF LUTEINIZING HORMONE IN PERIPUBERTAL FEMALE RATS
Authors: TER HAAR M. B. , WILSON CATHERINE A. 
Published: December 2008

*A.R.C. Institute of Animal Physiology, Babraham, Cambridge, CB2 4AT, and ‡Department of Physiology, Royal Veterinary College, London, NW1 OTU
(Received 28 March 1978)
Ovulation can be induced precociously in the prepubertal female rat by the administration of pregnant mare serum gonadotrophin (PMSG), provided that the animal weighs over 60 g (Wilson, Endersby & McDonald, 1974). The hormonal changes brought about by this treatment have been studied (J. C. Buckingham, M. B. ter Haar, A. S. McNeilly & C. A. Wilson, data to be published) and it has been found that the preovulatory concentrations of radioimmunoassayable luteinizing hormone (LH) varied according to the antiserum used. These findings are described in the present communication.
Female Sprague–Dawley rats (Tuck & Sons, Rayleigh, Essex) were brought into the department on day 21 of life, kept under conditions of controlled lighting (lights on 05.00–19.00 h) and provided with pelleted rat diet (No. 86, Dixon &
PLASMA CONCENTRATIONS OF LUTEINIZING HORMONE, TESTOSTERONE AND ANDROSTENEDIONE IN CASTRATED AND ADRENALECTOMIZED BULL CALVES
Authors: BASS J. J. , PETERSON A. J. , PAYNE E. 
Published: December 2008

Ministry of Agriculture and Fisheries, Research Division, Ruakura Agricultural Research Centre, Hamilton, New Zealand
(Received 17 April 1978)
An increase in the plasma concentration of luteinizing hormone (LH) occurs in response to castration in bull calves aged 1–4 months; this response is of similar magnitude to that seen in cattle castrated as adults (Odell, Hescox & Kiddy, 1970). In bull calves castrated at birth, however, there is no increase in the plasma concentration of LH until after 28 days of age (Bass, Peterson, Payne & Jarnet, 1977). In other species a range of responses to castration has been reported. Gonadectomy of male guinea-pigs 0–35 days after birth produces an increase in the plasma concentration of LH similar to that observed in guineapigs castrated as adults (Donovan, ter Haar, Lockhart, MacKinnon, Mattock & Peddie, 1975). In contrast, the castration of young male macaques does not cause an immediate increase in the
PLASMA CONCENTRATIONS OF 25-HYDROXY VITAMIN D IN PREGNANT AND LACTATING EWES AND FOETAL AND NEWBORN LAMBS
Authors: BARLET J.-P. , ARGEMI B. , DAVICCO MARIE-JEANNE , LEFAIVRE J. 
Published: December 2008

I.N.R.A., Theix, 63110 Beaumont, France and Groupe Hospitalier de la Timone, 13385 Marseille, France
(Received 31 May 1978)
Very little information is available concerning interrelationships between maternal and foetal concentrations of 25-hydroxy vitamin D3 (25-OHD3; Hillman & Haddad, 1974; Ross, Care, Pickard, Peacock & Robinson, 1976; Weisman, Sapir, Harell & Edelstein, 1976). This paper describes the concentrations of 25-OHD3 in the plasma of pregnant and lactating ewes and their foetal and newborn lambs.
Five ewes bearing single lambs were selected by radiography performed on day 100 of gestation in winter. The daily intakes of calcium, phosphate and magnesium for each animal were respectively, 11, 7 and 2 g. From day 26 pre partum until day 4 post partum, blood samples were collected through catheters implanted on day 115 of gestation in the left foetal and maternal carotid arteries (Mellor & Matheson, 1975). Plasma concentrations of 25-OHD3
EFFECT OF CORTICOTROPHIN ON CORTISOL SECRETION IN CASTRATED RHESUS MONKEYS
Authors: FARVER C. F. , DE WIED D. , TOIVOLA P. T. K. 
Published: December 2008

Wisconsin Regional Primate Research Center, University of Wisconsin, Madison, Wisconsin 53706, U.S.A.
(Received 22 May 1978)
In a wide variety of species corticotrophin (ACTH) is known to stimulate the synthesis and secretion of adrenocortical steroids. Studies with rhesus monkeys have shown that these responses can be affected by a number of factors including the method of handling and the type of physical restraint (Mason, 1959). In addition, androgens may depress plasma levels of glucocorticoids in primates (Brown & Migeon, 1956; Huis in't Veld, Louwerens & van den Spek, 1960). It was therefore decided to study the response of plasma cortisol to ACTH without these neural or hormonal influences. This report describes the effects of ACTH on castrated rhesus monkeys adapted to chronic restraint.
Four chair-restrained, orchidectomized rhesus monkeys (Macaca mulatta) bearing chronic indwelling venous catheters were used as experimental subjects and were housed, maintained and subjected to blood sampling as
UTILIZATION OF [26-14C]CHOLESTEROL BY HUMAN FOETAL ADRENAL GLANDS IN VITRO
Authors: GUNASEGARAM R. , PEH K. L. , CHEW P. C. T. , KARIM S. M. M. , RATNAM S. S. 
Published: December 2008

Department of Obstetrics and Gynaecology, University of Singapore, Kandang Kerbau Hospitalfor Women, Singapore 8, Republic of Singapore
(Received 3 May 1978)
From the previous studies of Bloch & Benirschke (1959, 1962) and Plotz, Kabara, Davis, LeRoy & Gould (1968) it appears that at mid-term, human foetal adrenal glands are capable of synthesizing C21- and C19-steroids de novo from acetate and cholesterol. Villee, Engel, Loring & Villee (1961), however, incubated slices and homogenates of foetal adrenal gland with [2-14C]acetate or [4-14C]cholesterol and could not demonstrate the incorporation of radioactivity into these steroids. Moreover, perfusion studies by three groups of investigators indicated only minute conversions of the same radioactive substrates into neutral steroids in the foetal adrenal glands (Solomon, Bird, Ling, Iwamiya & Young, 1967; Telegdy, Weeks, Archer, Wiqvist & Diczfalusy, 1970a; Telegdy, Weeks, Lerner, Stakemann & Diczfalusy, 1970b). It is widely believed that steroid hormones are normally synthesized from acetate via
UTERINE TISSUES FROM PREGNANT GOATS PRODUCE 6-OXO-PROSTAGLANDIN F1α IN VITRO
Authors: MITCHELL M. D. , FLINT A. P. F. , HICKS B. R. , KINGSTON E. J. , THORBURN G. D. , ROBINSON J. S. 
Published: December 2008

Nuffield Department of Obstetrics and Gynaecology, University of Oxford, John Radcliffe Hospital, Headington, Oxford, 0X3 9DU
(Received 21 July 1978)
It now seems likely that prostaglandins play an important role in the mechanisms of parturition in many species (Flint & Hillier, 1976; Thorburn, Challis & Robinson, 1977), including the goat (Thorburn, Nicol, Bassett, Shutt & Cox, 1972; Currie & Thorburn, 1977). This evidence has been further strengthened by the demonstration of the production of prostaglandins in vitro by uterine tissues from goats during late pregnancy (Mitchell, Flint, Robinson & Thorburn, 1978b). The recent discovery of prostacyclin (Moncada, Gryglewski, Bunting & Vane, 1976) has added a new dimension to prostaglandin research since in some biological systems it has a greater potency than other prostaglandins (Moncada et al. 1976; Omini, Moncada & Vane, 1977). Prostacyclin is highly unstable in aqueous media and degrades spontaneously to 6-oxo-prostaglandin F1α (6-oxo-PGF1α; Johnson, Morton, Kinner, Gorman,