bluuebunny/crossref_metadata_2025_split huggingface dataset:
EFFECTS OF CASTRATION AND TESTOSTERONE, DIHYDROTESTOSTERONE OR OESTRADIOL REPLACEMENT TREATMENT IN NEONATAL RATS ON MOUNTING BEHAVIOUR IN THE ADULT
Authors: SÖDERSTEN P. , HANSEN S. 
Published: December 2008

Castration of rats on the day of birth abolished the capacity to ejaculate and reduced the capacity to show intromissions in response to testosterone propionate (TP) treatment in adults. Day 10 castrated rats treated daily with oil or day 0 castrated rats treated daily with testosterone benzoate (TB) during the first 10 days of life achieved intromissions and ejaculation after TP treatment in adulthood. Treatment of day 0 castrated rats with a high dose of TB during the first 10 days of life enhanced their capacity to ejaculate in response to TP treatment in adulthood to a level above that of day 10 castrated rats given oil in infancy and similarly treated with TP as adults.
Castration on the day of birth greatly reduced the increase in penis weight and the development of cornified papillae on the glans penis which were seen in day 10 castrated rats after TP treatment in adulthood. These peripheral effects of neonatal testicular secretions are reversed by neonatal treatment of day 0 castrated rats with TB.
Daily treatment of day 0 castrated rats with dihydrotestosterone benzoate (DHTB) during the first 10 days of life facilitated the increase in weight of the penis and the development of cornified papillae on the glans penis but did not enhance the capacity to ejaculate in response to TP treatment in adulthood. Daily treatment of day 0 castrated rats with oestradiol benzoate (OB) during the first 10 days of life facilitated ejaculation without increasing penis sensitivity to TP in adulthood. Combined treatment of the neonate with OB and DHTB was no more effective in facilitating ejaculation in the adult than was OB alone. Neonatal treatment with OB was considerably more potent than neonatal treatment with TB in enhancing ejaculatory behaviour in adulthood.
It is suggested that both the inhibition of the development of lordosis behaviour and the facilitation of the development of mounting behaviour by testicular secretions in newborn rats may be dependent upon, but variously sensitive to, the amount of oestradiol formed in the brain from testosterone in the blood during the first 10 days of life.
METABOLISM OF ANDROSTENEDIONE IN SKIN AND SERUM LEVELS OF GONADOTROPHINS AND ANDROGENS IN PREPUBERTAL BOYS WITH HYPOSPADIAS
Authors: SVENSSON JAN , ENEROTH PETER , GUSTAFSSON JAN-ÅKE , RITZÉN MARTIN , STENBERG ÅKE 
Published: December 2008

The metabolism of 4-[1,2-3H]androstene-3,17-dione in the prepuce, axillary skin and skin from the arm was investigated in 27 boys operated for phimosis (controls) and 13 unselected boys with hypospadias (a congenital defect of the male urethra). In all types of skin investigated, androstenedione was metabolized to 5α-androstane-3,17-dione, 3α-hydroxy-5α-androstan-17-one, 3β-hydroxy-5α-androstan-17-one and testosterone. Conversion to testosterone was found in the prepuce of two out of 11 boys with hypospadias.
Mild forms of hypospadias in the age group 1–4 years had a higher level of 5α-reductase activity in the prepuce than controls in the same age group (P < 0·05); no such differences were found in the few severe cases of hypospadias in this group. No other differences in 5α-reductase activity were found between hypospadic boys and controls. The ratio of 5α-reductase activity in the prepuce: 5α-reductase activity in skin from the arm was significantly higher (P<0·05) in hypospadic boys than in controls in the age group 1–4 years.
Serum levels of LH and FSH were the same in normal and hypospadic boys but the concentration of prolactin in the serum was lower in boys with hypospadias compared with control subjects in the age group 1–4 years (P<0·005). No differences were found in serum concentrations of androstenedione, testosterone, oestradiol and testosterone-binding globulin.
EFFECT OF ALDOSTERONE ON URINE COMPOSITION IN THE CHRONICALLY CANNULATED OVINE FOETUS
Authors: LINGWOOD BARBARA , HARDY K. J. , COGHLAN J. P. , WINTOUR E. MARELYN 
Published: December 2008

* Department of Physiology, University of Melbourne, Parkville, Victoria 3052, Australia, † Department of Surgery, Austin Hospital, Studley Road, Heidelberg, Victoria 3084, Australia, and ‡ Howard Florey Institute of Experimental Physiology and Medicine, University of Melbourne, Parkville, Victoria 3052, Australia
(Received 19 October 1977)
Aldosterone is present in the peripheral blood of ovine foetuses from at least 60 days until term at 147 ± 5 days (Wintour, Brown, Denton, Hardy, McDougall, Oddie & Whipp, 1975). To determine the biological significance of this steroid in the foetus, infusions of aldosterone were made into foetuses bearing chronic vascular and bladder cannulae and the urinary sodium: potassium Na+: K+) ratio was measured before, during and after infusion. Silastic cannulae (0·76 mm internal diameter, 1·65 mm outer diameter) were placed 6–8 cm into the left carotid arteries and right jugular veins of seven ovine foetuses between 86 and 120 days of gestation and a
EFFECT OF PERINATAL OESTROGEN ON THE PRETREATMENT REQUIRED FOR MOUSE MAMMARY LOBULAR FORMATION IN VITRO
Authors: WARNER M. R. 
Published: December 2008

Morphological differentiation was enhanced in mammary glands from mice injected with oestradiol as neonates both in vivo, after 9 days of pretreatment with oestrogen and progesterone, and in vitro, either after 6 or 9 days of pretreatment and on all hormone supplements, or after culture with oestradiol, progesterone, aldosterone, insulin and thyroxine with or without prolactin and growth hormone. These hormone combinations further enhanced development, whereas culture with insulin and thyroxine did not.
Differentiation in vitro was least on medium containing insulin + thyroxine, and was greatest on the complete medium (insulin, thyroxine, growth hormone, prolactin, aldosterone, progesterone and oestradiol). An intermediate degree of differentiation occurred when growth hormone and prolactin were omitted from the complete medium.
Differences in lobule formation between oestrogen-treated and control mice were probably ovary-dependent at the dose used (25 μg/day), since pretreatment with oestradiol and progesterone was necessary to reveal them.
Enhanced hormone sensitivity of murine mammary tissues exposed to oestradiol early in life may be related to subsequent enhanced dysplastic potential of the tissue and provides a further basis for caution in the administration of steroids to immature individuals.
STIMULATORY AND INHIBITORY EFFECTS OF OVARIAN STEROIDS ON GONADOTROPHIN SECRETION IN OVARIECTOMIZED RATS AFTER ANTERIOR HYPOTHALAMIC DEAFFERENTATION
Authors: TALEISNIK S. , CALIGARIS L. , BELTRAMINO C. , CÁCERES A. 
Published: December 2008

The effect of frontal hypothalamic deafferentation on the release of LH and FSH was studied in ovariectomized rats. Frontal cuts were placed just in front of the arcuate nucleus, at the posterior border of the optic chiasma (RCS), at the level of the anterior commissure (POS) and in front of the optic chiasma (PCS). Animals with RCS and POS cuts showed vaginal smears with persistent cornification; the other groups had irregular cycles.
The concentrations of LH and FSH in the serum increased after ovariectomy in deafferentated animals, but after 4 weeks the levels were lower than in the animals without hypothalamic lesions except for the PCS group. The more caudally that the cuts were located, the lower were the concentrations of hormones in the serum. The injection of repeated doses of oestradiol benzoate resulted in a decrease in serum gonadotrophin of both rats without hypothalamic lesions and RCS rats. Although a greater decrease was observed in the lesioned than in the intact rats, it is believed that such an effect does not indicate an increased sensitivity of deafferentated animals to this steroid.
The stimulatory effect of progesterone on LH and FSH release was studied in ovariectomized rats primed with oestradiol benzoate. The responses were unchanged in PCS animals but failed to occur in POS and RCS rats. Measurement of the level of gonadotrophin-releasing hormone in frontal hypothalamic slices from RCS animals showed a decreased level behind the cut and an increased one in front of it, suggesting that perikarya located in front of the section were sending their axons to the mediobasal hypothalamus. It is believed that the blockade of the stimulatory effect on gonadotrophins by frontal hypothalamic deafferentation is due to the transection of these axons. Cuts placed immediately in front of the arcuate nucleus, however, permitted progesterone-induced gonadotrophin release because of incoming neurones containing gonadotrophin-releasing hormone, which end in structures immediately rostral to the cut. The results indicate that effects of both inhibitory and stimulatory ovarian steroid feedback are impaired by frontal hypothalamic deafferentation.
URINARY CALCIUM EXCRETION IN HYPERPROLACTINAEMIA
Authors: HIPKIN L. J. , DAVIS J. C. , DIVER M. J. 
Published: December 2008

Sub-department ofEndocrine Pathology, Alder Hey Hospital, Eaton Road, Liverpool, LI2 2AP
(Received 12 September 1977)
Injections of ovine prolactin into normal subjects and certain patients increases the urinary excretion of calcium (McCalister & Welbourn, 1962; Beck, Gonda, Hamid, Morgen, Rubinstein & McGarry, 1964) and hypercalcaemia as well as hypercalcinuria is produced after administration of prolactin to experimental animals (Mahajan, Robinson & Horrobin, 1974). The levels of calcium in the serum and urine of patients with hyperprolactinaemia have therefore been studied.
Fourteen patients (one man, 13 women) were selected on the basis of raised levels of prolactin in the plasma. Clinical details are shown in Table 1. None of the patients had primary hypothyroidism and none was taking drugs except the man (S.B.), who was on cortisone and thyroxine replacement therapy. During the study, patients had their normal diet either at home or in hospital. Plasma prolactin was estimated by radioimmunoassay
STEROIDOGENESIS BY CULTURED GRANULOSA CELLS ASPIRATED FROM HUMAN FOLLICLES USING PREGNENOLONE AND ANDROGENS AS PRECURSORS
Authors: FOWLER R. E. , FOX N. L. , EDWARDS R. G. , WALTERS D. E. , STEPTOE P. C. 
Published: December 2008

SUMMARY
Human granulosa cells from Graafian follicles aspirated 3–4 h before the expected time of ovulation were incubated with various steroid substrates, including pregnenolone, androstenedione, testosterone and dehydroepiandrosterone (DHA). Steroid production after 3 and 10 h of incubation was determined by radioimmunoassay.
Progesterone and 17α-hydroxyprogesterone were the major products of granulosa cells in control short-term cultures with endogenous substrates. The addition of pregnenolone increased the synthesis of progesterone and 17α-hydroxyprogesterone compared with the controls, although the response varied considerably between paired short-term cultures. Little or no oestradiol-17β was produced from endogenous precursors or short-term cultures to which pregnenolone had been added; one follicle, however, produced similar amounts of oestradiol-17β in the control cultures and after incubation with pregnenolone.
When granulosa cells were cultured with various amounts of androstenedione, DHA or testosterone, large amounts of oestradiol-17β were produced, especially in short-term cultures in which larger amounts of substrate were added. Progesterone production continued and progesterone was synthesized more rapidly or in greater amounts in some short-term test cultures than in the controls.
The results indicate that human granulosa cells are one source of oestradiol-17β during the preovulatory phase. The data support the two-cell theory for oestradiol synthesis, for granulosa cells do not appear to undertake steroid conversion via the 5-unsaturated pathway, but aromatize androgens known to be produced by thecal cells. It is also suggested that either androgens or oestradiol-17β stimulate progesterone production by granulosa cells, at least in vitro.
PARTIAL SYNCHRONY OF THE OESTROUS CYCLES OF RATS INTRODUCED TO A NEW ENVIRONMENT
Authors: SHIRLEY BARBARA 
Published: December 2008

SUMMARY
Partial synchronization of oestrous cycles was observed in Sprague–Dawley rats with both 4 and 5 day cycles. In groups of rats exhibiting a synchrony of cycles, the number of animals that came into oestrus 4 or 5 days (approximately one cycle) after they were placed in a new environment was significantly greater than the number expected to be in oestrus if cycling was random. An environmental influence was considered to be responsible for the synchrony of the oestrous cycles but a specific stimulus for their synchronization was not identified. Initiation of vaginal smearing was considered to be a factor contributing to cycle synchrony. The introduction of rats to light–darkness cycles and their removal from the presence of other female rats were stimuli tested for their effectiveness in initiating new cycles, and causing the cycles to be synchronized as a consequence, but, when tested, neither of these environmental changes was found to initiate the observed synchrony of cycles.
MEMBRANES FROM A TRANSPLANTABLE OSTEOGENIC SARCOMA RESPONSIVE TO PARATHYROID HORMONE AND PROSTAGLANDINS: REGULATION OF ADENYLATE CYCLASE AND OF HORMONE METABOLISM
Authors: CRAWFORD A. , HUNT N. H. , DAWBORN J. K. , MICHELANGELI V. P. , MARTIN T. J. 
Published: December 2008

SUMMARY
Adenylate cyclase activity in particulate fractions from a transplantable rat osteogenic sarcoma was stimulated in a dose-dependent manner by prostaglandins E1 and E2 (PGE1 and PGE2) and parathyroid hormone (PTH). Prostaglandin F2α was active at a high concentration (3 × 10− 4 mol/l). Pretreatment of membranes with collagenase plus hyaluronidase reduced the magnitude of the PTH effect but did not affect the size of the PGE1 effect.
Guanosine 5′-triphosphate and its synthetic analogue 5′-guanylylimidodiphosphate (Gpp(NH)p) activated adenylate cyclase in particulate preparations from the osteogenic sarcoma. The latter agent produced much larger effects, although the concentrations required for half-maximal enzyme activation were the same for both agonists (approximately 2 × 10−6 mol/l). The effects of PTH and Gpp(NH)p were supra-additive at some concentrations of hormone. The effects of PGE1 and Gpp(NH)p were supra-additive at all hormone concentrations tested. Pre-incubation of membrane particles for 6 min with PTH produced an enzyme activation which was not reversed by dilution through washing; pre-incubation with PGE1 did not produce this effect. The response of membrane adenylate cyclase to Gpp(NH)p (10−4 mol/l) was 75% greater in preparations pre-incubated with PTH than in membranes pre-incubated in buffer alone or in buffer containing PGE1. The basal rate of cyclic AMP production in the adenylate cyclase assay system decreased over a 35 min incubation period. This decrease was prevented by addition of PTH or PGE1. Addition of NaF or Gpp(NH)p produced a steady increase in the rate of production of cyclic AMP with time.
Membrane preparations did not reduce the biological activity of PTH and did not degrade 125I-labelled PTH.
The results demonstrate that the PTH- and PGE-responsive adenylate cyclases of the osteogenic sarcoma have distinctly different properties and that particulate preparations of the tumour do not metabolize PTH.
A METHOD TO STUDY TEMPORAL CHANGES IN ADRENAL ACTIVITY IN RELATION TO SEXUAL STATUS IN THE FEMALE LABORATORY RAT
Authors: PHILLIPS J. G. , POOLSANGUAN W. 
Published: December 2008

There is a temporal relationship between the secretory activity of the rat adrenal gland and the stage of the oestrous cycle. In previous studies, adrenal venous blood has been sampled, but because of the stress of a lengthy operation, the gland is subjected to maximum stimulation. A new surgical approach has been developed in which samples of adrenal venous blood are taken within 3 min of contact. A competitive binding radioassay was used to determine the level of corticosterone in samples of plasma of both adrenal venous and peripheral arterial origin obtained before (3 min) and after (15 min) the onset of (presumably) ACTH-induced secretion. A reassessment of adrenal function indicated that adrenal activity peaked in pro-oestrus with higher values in the afternoon than the morning and both values were significantly higher than at any other stage in the oestrous cycle. The variations in the concentration of corticosterone in adrenal venous plasma were reflected by a similar pattern of variation in the level of corticosterone in peripheral arterial plasma. In samples of adrenal venous plasma obtained at 15 min, the level of corticosterone was approximately 25 times higher than the basal value during pro-oestrus and approximately 140 times higher than the values during the other stages of the cycle; for peripheral arterial blood the values were eight and 22–30 times higher respectively, without any significant difference when samples of either type of blood were obtained under stress. This indicates maximum stimulation by endogenous ACTH.
Results obtained after treatment of ovariectomized rats with progesterone and/or oestradiol and the fact that LH, but not ACTH, plays a stimulatory role in the non-stressed metoestrous animal, suggest that the peak of adrenal activity at the time of pro-oestrus might be biphasic: in the morning it is influenced by a high level of oestrogen and a low level of progesterone; in the afternoon this balance is reversed. The effect is secondary to the surge of LH which may have a direct effect on the peak of adrenal activity at this critical period.
PURIFICATION AND SOME PROPERTIES OF OVINE PLACENTAL LACTOGEN
Authors: REDDY S. , WATKINS W. B. 
Published: December 2008

A method has been described for the purification of ovine placental lactogen (oPL) involving the use of freshly obtained sheep foetal cotyledons. Tissue was extracted with 0·1 m-ammonium bicarbonate and the supernatant fraction, adjusted to pH 7, was brought to 60% saturation with ammonium sulphate. The resulting precipitate was then subjected to a sequence of chromatographic steps using columns of Sephadex G-100 and carboxymethylcellulose. During each stage of the purification, the lactogenic activity was monitored with a pregnant rabbit mammary gland radioreceptor assay. The yield of oPL corresponded to 8 mg/kg wet foetal tissue and the oPL possessed lactogenic activity equivalent to 1 mg ovine prolactin/mg protein and GH-like activity equivalent to 0·8 mg human GH/mg protein. The biological activity of oPL was confirmed using a rabbit intraductal mammary gland assay in vivo.
After polyacrylamide gel electrophoresis at pH 8·9, oPL was resolved into one major band (isoelectric point 8·2–8·4) and four minor components, which were thought to be deamidation products of oPL. Microimmunoelectrophoresis and immunodiffusion studies confirmed that the preparation of oPL was free from serum protein contaminants.
CIRCADIAN VARIATIONS IN CORTISOL CONCENTRATIONS IN THE PLASMA OF FEMALE RHESUS MONKEYS
Authors: LESHNER A. I. , TOIVOLA P. T. K. , TERASAWA E. 
Published: December 2008

Wisconsin Regional Primate Research Center, University of Wisconsin, Madison, Wisconsin 53706, U.S.A.
(Received 25 January 1978)
Diurnal variations in the adrenal secretion of glucocorticoids have been described in a wide range of species. Among primates, most attention has been devoted to man (e.g. Krieger, 1970; Rose, Kreuz, Holaday, Sulak & Johnson, 1972), although the secretion of cortisol in the male rhesus monkey has also been examined (e.g. Michael, Setchell & Plant, 1974; Holaday, Meyerhoff & Natelson, 1977). We present here a report of circadian variations in the concentration of cortisol in the plasma throughout the menstrual cycle of the female rhesus monkey.
Three intact female rhesus monkeys (Macaca mulatta) were adapted to chronic restraint in primate chairs for several months. After confirmation of normal menstrual cycles, a chronic indwelling catheter (Silastic Medical Grade Tubing, 20-gauge, Dow Corning) was inserted. The catheter was placed into the right atrium via the internal
EFFECTS OF AGE AND OVARIAN FUNCTION ON THE PITUITARY–THYROID SYSTEM IN FEMALE RATS
Authors: CHEN H. J. , WALFISH P. G. 
Published: December 2008

SUMMARY
The effects of ovariectomy and ovariectomy and treatment with oestradiol benzoate (OB) on the basal concentration of thyrotrophin (TSH), the total concentrations and concentrations of free tri-iodothyronine (T3) and thyroxine (T4), and the concentrations of TSH, T3 and T4 observed after treatment with thyrotrophin releasing hormone (TRH) were studied in old (16–17 months of age) constant oestrous and young (3–4 months of age) oestrous rats. The untreated old control rats had significantly (P< 0·001) lower basal total T4 concentrations and percentage and absolute concentrations of free T4 and lower percentage and absolute concentrations of free T3 than untreated young rats. The basal levels of TSH in these two groups were similar and the increases in TSH after injection of TRH were identical. Two weeks after ovariectomy, no significant additional differences in hormone concentrations between old and young rats were observed. However, release of TSH induced by TRH was increased by three- to fourfold in old rats after ovariectomy compared with nine- to tenfold in young ovariectomized rats (P<0·01). Basal T4 concentrations remained unchanged in old ovariectomized rats treated for 7 days with 2 μg OB/day compared with both intact and ovariectomized rats. However, T4 concentrations in OB-treated young rats were significantly (P<0·001) reduced. Treatment with OB significantly increased both basal and TRH-induced T3 and TSH levels in old and young rats although the young rats showed a greater response (P<0·001). Two hours after injection of TRH, serum T3 concentrations in old rats increased only after OB treatment and not after ovariectomy alone or in intact rats, whereas T3 concentrations rose in all three groups of young animals.
These results indicate that (1) older female rats have lower total T4, free T4 and free T3 concentrations and a lower TSH response to TRH, (2) OB treatment in young rats suppresses serum T4 but increases serum T3 and results in a greater TSH response to TRH and (3) at least one of the mechanisms accounting for the alterations in thyroid function observed in the older female rat, in addition to possible concomitant primary thyroid gland hypofunction, is a hyporesponsiveness of pituitary thyrotrophs to both endogenous negative feedback signals from low serum thyroid hormone concentrations and exogenous TRH stimulation.