bluuebunny/crossref_metadata_2025_split huggingface dataset:
THE EFFECT OF PINEAL METHOXYINDOLES ON RAT VAGINAL OPENING TIME
Authors: COLLU R. , FRASCHINI F. , MARTINI L. 
Published: December 2008

SUMMARY
Melatonin and 5-methoxytryptophol, the two methoxyindoles of pineal origin, were injected into a lateral ventricle of the brain of immature female rats. Treatment was started on the 25th day of age and terminated when the vagina opened. The injection of both methoxyindoles resulted in a statistically significant delay in vaginal opening. Since previous experiments had shown that melatonin specifically inhibits secretion of luteinizing hormone and that 5-methoxytryptophol specifically blocks release of follicle-stimulating hormone, the present results support the hypothesis that the onset of sexual maturation needs a balanced secretion of both gonadotrophins.
CYTOLOGICAL CHANGES IN THE MOUSE ANTERIOR PITUITARY AFTER NEONATAL THYMECTOMY: A LIGHT AND ELECTRON MICROSCOPICAL STUDY
Authors: BIANCHI ELENA , PIERPAOLI W. , SORKIN E. 
Published: December 2008

SUMMARY
A detailed light and electron microscope examination of the anterior pituitary gland of mice at different times after neonatal thymectomy was performed. Neonatal removal of the thymus resulted in a progressive increase in the number of somatotrophic hormone-producing cells showing characteristic changes represented by extremely distended cisternae of the endoplasmic reticulum and reduction in the number of hormone granules. These modifications were not observed in sham-operated controls or in neonatally splenectomized mice. The functional significance of these changes in relation to thymectomy and the significance of somatotrophic hormone for the development of the thymus and for immunological maturation is discussed. It is suggested that somatotrophic hormone and possibly other hormones determine certain specific steps of differentiation of precursor cells to immunocompetent cells and that the thymus is an endocrine target gland of somatotrophic hormone.
TESTOSTERONE BIOSYNTHESIS IN THE DESERT MOUSE, ACOMYS CAHIRINUS
Authors: BEDRAK E. , SAMOILOFF V. , FINKELSTEIN Z. 
Published: December 2008

SUMMARY
Testosterone synthesis was studied in Acomys cahirinus by incubation of its testis with radioactive substrates. In comparison with other rodents, the Acomys testis was found to have a lower 17β-hydroxysteroid oxidoreductase activity, whereas the activity of 20α-hydroxysteroid oxidoreductase was high. The accumulation of 5-ene-3β-hydroxy metabolites suggested that biosynthesis proceeded preferentially by the 4-ene route. This was confirmed by the simultaneous incubation of [3H]5-ene-3β-hydroxysteroids and [14C]4-en-3-oxosteroids. The predominant route of biosynthesis would, therefore, appear to be: pregnenolone → progesterone → 17α-hydroxyprogesterone → androstenedione → testosterone.
IMMUNOASSAY OF HUMAN LUTEINIZING HORMONE USING UNIVALENT RADIOACTIVE ANTIBODIES
Authors: MILES L. E. M. , HARTREE ANNE STOCKELL 
Published: December 2008

SUMMARY
Univalent antibody fragments were isolated from a papain-digested antiserum to human chorionic gonadotrophin. The univalent antibody fragments were purified, iodinated with 125I and used in a sensitive immunoradiometric assay of human luteinizing hormone. Unlike intact divalent antibodies, the univalent radioactive antibody fragments cannot simultaneously bind to both soluble antigen and antigen-immunoadsorbent.
THE ACTIVITY OF HUMAN FOLLICLE-STIMULATING HORMONE PREPARATIONS AS MEASURED BY A RESPONSE IN VITRO
Authors: RYLE MARGARET 
Published: December 2008

SUMMARY
Experiments were carried out with two highly purified preparations of human follicle-stimulating hormone (FSH), of pituitary and urinary origin. The uptake of [3H]thymidine was used to measure the response of cultured infantile mouse ovaries. The activity of the pituitary FSH did not decline during 7 days' incubation in the standard culture conditions, nor was it reduced by the culture of infantile mouse ovaries in it. It did not stimulate increased thymidine uptake during the 1st day of culture. Thereafter the rate of thymidine uptake per ovary in response to pituitary FSH remained constant until the end of the 4-day culture period. The urinary FSH became progressively less effective after the 2nd day of incubation. The two preparations gave highly significant linear log dose—response curves in the range 0·01 to 0·64 i.u./ml. The results are discussed in relation to the mode of action of FSH.
INVOLVEMENT OF THE MACROPHAGE SYSTEM IN THE INVOLUTION OF THE MAMMARY GLAND IN THE ALBINO RAT
Authors: RICHARDS R. C. , BENSON G. K. 
Published: December 2008

SUMMARY
Adult female rats undergoing their first lactation were experimentally weaned by removing their pups on day 4 of lactation. The macrophages of the mammary gland were labelled with trypan blue or horseradish peroxidase. Treatment with trypan blue showed the macrophages to be present in the connective tissue stroma from the 4th day of lactation to the 5th day of involution. However, on day 6 of involution they were congregated around the remaining islets of alveoli. Other cells which took up the dye were found in the epithelium of the alveoli. They were few in number on day 4 of lactation, increased numerically during the first 2 days of involution, and decreased again by day 6 of involution. Since they took up the dye in a similar manner to the lymphocytes of the regional lymph node, it is believed that they were lymphocytes. Treatment with ICI 46,474 in no way affected the course of mammary involution up to day 6. Treatment with horseradish peroxidase on day 4 of lactation or day 2 of involution resulted in labelling of the macrophages, which were found scattered in the stroma. However, by the 4th and 6th day of involution the macrophages were found to a greater extent in and around the remaining islets of alveoli.
DNA POLYMERASE ACTIVITY IN MAMMARY GLAND OF VIRGIN MICE AFTER OVARIAN HORMONE TREATMENT
Authors: BANERJEE D. N. , BANERJEE M. R. , WAGNER JANICE 
Published: December 2008

SUMMARY
The effect of ovarian hormones on DNA polymerase activity in the mouse mammary gland was determined. The rate of [3H]thymidine triphosphate incorporation into DNA during incubation in vitro was used as a measure of DNA polymerase activity in the post-microsomal supernatant fraction of the mammary tissue. A negligible amount of DNA polymerase activity was present in the mammary tissue of ovariectomized mice which had no hormone treatment. Daily subcutaneous injections of 1 μg oestradiol-17β plus 1 mg progesterone induced a sixfold increase of DNA polymerase activity in the mammary tissue after two injections. A single intraperitoneal injection of the same dose also induced a similar rise of DNA polymerase activity and the effect was evident within hours after the treatment. The results provide evidence that stimulation of cellular biosynthesis by the growth-promoting ovarian hormones is associated with the activation of a specific enzyme involved in DNA replication.
ANALYSIS OF MILK SECRETED SPONTANEOUSLY BY VIRGIN RATS BEARING INDUCED MAMMARY TUMOURS
Authors: HALLOWES R. C. , LEWIS DOREEN J. 
Published: December 2008

SUMMARY
Biochemical and immunological studies were performed on milk secreted spontaneously by 1-yr-old virgin female Sprague—Dawley rats. They had received 30 mg 9,10-dimethyl-1,2-benzanthracene when 50 days old and most had mammary gland tumours. No milk secretion was found specifically in any of these tumours. The fat content of the secretion was twice that of post-partum milk and slight differences were demonstrated in the saturated fatty acid composition. The protein concentration was doubled but both casein and milk plasma proteins were identical to those of post-partum milk. The lactose concentration was one quarter that of post-partum milk but similar milk specific carbohydrates were present. Lactate dehydrogenase isoenzymes were quantitatively similar in each. It was shown that the secretion by virgin rats closely resembled post-partum milk.
EFFECTS OF VOLUME AND DISTRIBUTION OF MILK ON THE OXYTOCIN-INDUCED CONTRACTION OF THE LACTATING RAT MAMMARY GLAND IN VIVO
Authors: DeNUCCIO D. J. , GROSVENOR C. E. 
Published: December 2008

SUMMARY
Milk was added intraductally in 0·2 ml increments to previously emptied mammary glands in rats. Direct microscopic observations of the glands showed that each increment of milk did not distribute evenly either within a single lobule or among lobules. Increase of the intramammary pressure either by i.v. injection of oxytocin or by compression of the gland between thumb and forefinger, distributed the milk more evenly within the gland. These observations led to the routine injection of 1·6–3·2 mu. oxytocin in order to distribute each increment of milk evenly throughout the gland. The intramammary pressure response of the gland to different doses of oxytocin was then determined. The rises in intramammary pressure above equilibrium pressure in response to 0·8 and 1·6 mu. oxytocin increased fourfold on average with increasing gland volume over the compliant portion of the static pressure-volume curve. The slopes of the dose oxytocin-intramammary pressure response lines became progressively steeper and shifted to the left as the volume of the mammary gland increased, indicating a progressive reduction in the dose of oxytocin required to elicit a given response. No differences were noted between rats lactating for 9–13 days and those lactating for 20–24 days. In a related study the duct system of the rat gland was found to contain little fluid even after 8 h of non-suckling, though it became filled swiftly after a single i.v. injection of oxytocin. Non-suckling for 16–24 h was required to overcome passively the resistance to entry of milk from the alveoli.
RATES OF INCORPORATION OF [3H]LEUCINE INTO PROTEIN OF THE PARS INTERMEDIA OF THE PITUITARY IN THE AMPHIBIAN XENOPUS LAEVIS AFTER CHANGE OF BACKGROUND COLOUR
Authors: WHUR P. , WEATHERHEAD B. 
Published: December 2008

SUMMARY
Xenopus were kept on, and transferred between, black or white back-grounds before incubating the pars intermedia and sometimes other parts of the pituitary with [3H]leucine. The rates of incorporation of label were assessed either by liquid scintillation counting of trichloroacetic acid precipitates or quantitative analysis of autoradiographs. Inhibition of incorporation of label was achieved after incubation with puromycin, showing that the label was associated with newly synthesized peptide material. The rates of incorporation of label into pars distalis and pars nervosa were not significantly different in animals from black or white back-grounds. However, pars intermedia from animals on a black background incorporated label at three to six times the rate of animals from a white background. In animals kept for some days on a white background and then transferred to a black background the rate of incorporation began to rise within a few minutes and reached the new higher level after several hours. In animals transferred from a black to a white background, however, no decline in rate was detected until 2 days after the transfer, but by 3 days the rate had returned to the white background level. The timing of these changes bears no relationship to the timing of changes, reported elsewhere, in the ultrastructure of pars intermedia cells after changes in background colour. They are, on the other hand, similar to the timing of changes in the melanocyte-stimulating hormone content of pars intermedia and also to changes in the melanophore index.
METABOLISM OF PREGNENOLONE AND DEHYDROEPIANDROSTERONE BY HOMOGENIZED TISSUE FROM THE SEPARATED ZONES AND WHOLE ADRENAL GLANDS FROM NEWBORN ANENCEPHALIC INFANTS
Authors: COOKE B. A. , SHIRLEY I. M. , DOBBIE J. , TAYLOR PATRICIA D. 
Published: December 2008

SUMMARY
The metabolism of [3H]pregnenolone and [3H]dehydroepiandrosterone ([3H]DHA) by tissue from the separated zones and whole adrenal glands from newborn anencephalic infants was investigated.
Pregnenolone was metabolized by the whole gland homogenates mainly to pregnenolone sulphate and unconjugated 17α-hydroxypregnenolone and also to small amounts of DHA and dehydroepiandrosterone sulphate (DHAS). DHA was metabolized by the whole gland homogenates mainly to androstenedione and DHAS and small amounts of 11β-hydroxyandrostenedione.
Adrenal gland tissue from a 42-week-old anencephalic infant containing three histologically distinct zones in the adult cortex in addition to residual foetal zone had sulphokinase, 17α-hydroxylase, 17–20 lyase and 3β-hydroxy-steroid dehydrogenase/Δ4,5 unsaturated isomerase activity in each of these zones. These enzymes were also present in the adrenal adult zone of another anencephalic infant.
Omission of ATP from the incubation medium greatly reduced the conversion of DHA to DHAS in the homogenates and separated zones.
These results are discussed in relation to oestrogen biosynthesis in anencephaly and to foetal 4-en-3-oxosteroid synthesis in utero.
EFFECTS OF OESTROGEN AND PROGESTERONE ON THE DEVELOPMENT, OVIDUCTAL TRANSPORT AND UTERINE RETENTION OF EGGS IN HYPOPHYSECTOMIZED PREGNANT RATS
Authors: WU J. T. , DICKMANN Z. , JOHNSON D. C. 
Published: December 2008

SUMMARY
Hypophysectomy of rats on day 1 of pregnancy resulted in expulsion of most eggs from the uterus between days 5 and 6, delayed entry of eggs into the uterus, and retarded development of eggs.
Expulsion of eggs was prevented with daily injections of 2 mg progesterone. Other regimes of progesterone administration were also beneficial, but not as effective as daily injections.
Daily injections of 2 or 4 mg progesterone, or of progesterone plus oestrone, restored egg transport to normal, whereas a single injection of progesterone did not. Daily injections of small amounts of oestrone caused total disappearance of eggs from the reproductive tract.
The development of eggs was significantly improved with daily injections of progesterone plus oestrone, but not with progesterone alone.
Combined treatment with progesterone and oestrone caused premature shedding of the zona pellucida in mature blastocysts, young blastocysts, and morulae.
FEMALE SEXUAL BEHAVIOUR IN MALE GOLDEN HAMSTERS
Authors: TIEFER LEONORE , JOHNSON W. A. 
Published: December 2008

SUMMARY
Four groups of adult male hamsters were castrated and injected with either 6 μg oestradiol benzoate (OB), 100 μg OB, 6 μg OB plus 0·5 mg progesterone or 100 μg OB plus 0·5 mg progesterone. In repeated tests with virile males, all the injected males showed lordosis behaviour similar, but quantitatively inferior, to that of female hamsters. Uninjected controls showed no lordosis. There was no dose—response relationship between the two doses of oestrogen. Progesterone significantly facilitated the quantity and quality of lordosis behaviour shown. This is in contrast with previous reports of the absence of facilitation by progesterone in male rats. After cessation of hormone injections the animals continued to display the lordosis response for several weeks.
RECOVERY FROM LETHAL X-RAY DAMAGE DURING DELAYED IMPLANTATION IN THE RAT
Authors: WARD W. F. , MEYER R. K. , WOLF R. C. 
Published: December 2008

SUMMARY
Rats were exposed to either 300 or 500 röntgen (R) acute whole-body X-irradiation on the 5th day of delayed pregnancy induced by ovariectomy. From 0 to 8 days after irradiation, implantation was induced by the administration of oestrogen. Foetal survival to the 20th day of development was used as an index of radiation effect.
If oestrogen was given immediately after exposure to 300 R, or 12 h later, only 30–35% of the embryos survived, significantly less (P < 0·01) than the non-irradiated control values of 74–79%. When implantation was postponed for 24 h or more, embryonic survival ranged from 57 to 64% and was not significantly different from that of controls.
After exposure to 500 R X-irradiation, embryonic survival increased linearly from 2% to a maximum of 41% as the interval between irradiation and oestrogen administration increased from 0 to 48 h. Embryonic survival never reached control levels after 500 R, regardless of the interval between irradiation and implantation. The irradiation regimens also induced developmental abnormalities, doubled the incidence of dead foetuses (death at a late stage of development), and significantly reduced foetal and placental weights at autopsy.
The results confirm that recovery from potentially lethal X-irradiation damage can occur during delayed implantation, and demonstrate that both the extent and the rate of recovery are functions of the radiation dose.
THE ROLE OF GASTRIN AS A CALCITONIN SECRETAGOGUE
Authors: CARE A. D. , BATES R. F. L. , SWAMINATHAN R. , GANGULI P. C. 
Published: December 2008

SUMMARY
Our earlier observation that pentagastrin is a calcitonin (CT) secretagogue was confirmed and extended to include both synthetic human gastrin I and pure porcine gastrin II. The latter hormone was shown to stimulate the secretion rate of CT from thyroid preparations perfused in situ in anaesthetized pigs at concentrations (0·5 nmol/l) similar to those found after stimulation of gastrin production by a meat extract placed in the stomach (0·2 nmol/1). These concentrations of plasma gastrin are considerably less than those found in man in both pernicious anaemia and the Zollinger—Ellison syndrome, whereas the mean fasting plasma gastrin concentrations in normal human beings and pigs are similar. It is suggested that the comparatively high incidence of parathyroid hyperactivity in association with the Zollinger—Ellison syndrome may be a consequence of an increased CT secretion rate induced by hypergastrinaemia. Furthermore, the existence of a gastrointestinal—thyroid C cell system is proposed as an integral part of postprandial calcium homeostasis.
STEROID METABOLIC PATHWAYS IN THE OVARY OF THE CHINCHILLA (CHINCHILLA LANIGER)
Authors: TAM W. H. 
Published: December 2008

SUMMARY
The ovarian tissue components of the pregnant chinchilla were incubated with equimolar amounts of [7α-3H]pregnenolone and [4-14C]progesterone. The greater contribution by [7α-3H]pregnenolone than by [4-14C]progesterone towards the formation of 17α-hydroxyprogesterone and androstenedione, and the relatively high yields of 17α-hydroxypregnenolone and dehydroepiandrosterone showed that both the 4-ene and 5-ene pathways of steroid metabolism were used in the interstitial tissue. No significant amount of 17α-hydroxylation was observed in the primary and accessory corpora lutea. The results of kinetic investigations using [7α-3H]pregnenolone as substrate also demonstrated a precursor—product relationship between dehydroepiandrosterone and androstenedione in the interstitial tissue, but this was not apparent in the luteal tissue. The results indicated that the interstitial tissue was capable of synthesizing progesterone and oestrogens as major products, and that the lack of 17α-hydroxylation in the luteal tissue was a controlling factor ensuring the synthesis of progesterone as its principal hormonal product. A small amount of [4-14C]dehydroepiandrosterone was always isolated with a much larger amount of the tritiated compound. This implied the conversion of 14C-labelled 4-en-3-oxosteroids into 5-ene-3β-hydroxysteroids which has generally been regarded as impossible. The isolation of this product, which may be an artifact, and the possibility that progesterone and oestrogens may be synthesized by different cells (granulosa and theca lutein cells) in the corpus luteum, or that there may be a third pathway for oestrogen synthesis, as suggested by the results of the kinetic experiments, are discussed.
THE EFFECT OF DIAZEPAM ON PITUITARY FUNCTION IN MAN
Authors: HAVARD C. W. H. , SALDANHA V. F. , BIRD R. , GARDNER R. 
Published: December 2008

SUMMARY
The integrity of pituitary—adrenal function and growth hormone production was determined in 15 patients before and after treatment with diazepam (30 mg daily). There was no evidence of impairment; nor was the urinary excretion of catecholamines significantly altered. The reproducibility of the plasma corticosteroid response to insulin-induced hypoglycaemia was separately assessed and both the degree of fall in blood sugar and the rise in plasma corticosteroid level were found to be similar.
EXCRETION OF 15α-HYDROXYOESTRIOL AND OESTRIOL IN URINE OF NEWBORN INFANTS AND IN MATERNAL URINE BEFORE AND AFTER DELIVERY
Authors: HEIKKILÄ JORMA 
Published: December 2008

SUMMARY
The amounts of oestriol and 15α-hydroxyoestriol (oestetrol) were determined in 24-h urine samples collected from pregnant women before and after delivery. In addition, the concentrations of these oestrogens were estimated in the urine of the newborn infants born to these mothers. The excretion of both these oestrogens decreased exponentially in maternal urine after delivery, the rate of decrease being significantly slower for oestetrol. The concentration of oestriol and oestetrol in the urine of the newborn infants also fell rapidly after delivery, the reduction being a linear function of time. The concentration of oestetrol in the urine of the newborn infant was relatively high in comparison to that of oestriol, and during the first day of life was the same as in maternal urine before delivery.
LOCALIZATION OF FOLLICLE-STIMULATING AND LUTEINIZING HORMONES IN THE RAT TESTIS USING IMMUNOHISTOLOGICAL TESTS
Authors: CASTRO A. E. , ALONSO A. , MANCINI R. E. 
Published: December 2008

SUMMARY
Rabbit antisera to ovine follicle-stimulating (FSH) and luteinizing (LH) hormones were used in the indirect fluorescent antibody technique on sections of rat testis to detect intravenously injected FSH or LH. A direct method using ferritin-labelled rabbit anti-LH globulins was also performed on sections of testis from LH-injected rats. Follicle-stimulating hormone was localized in the Sertoli cells while LH appeared mainly in the interstitial and peritubular cells. These results agree with previous observations on the cellular distribution of both gonadotrophins in the rat testis.
THE BLOOD LEVELS OF OXYTOCIN DURING SUCKLING AND HAND-MILKING IN THE GOAT WITH SOME OBSERVATIONS ON THE PATTERN OF HORMONE RELEASE
Authors: McNEILLY A. S. 
Published: December 2008

SUMMARY
Thirty-six series of serial jugular blood samples were collected from 12 goats during suckling during the first 3 weeks of lactation and the transient appearance of oxytocin (5–86 μu./ml plasma) was detected in 24 of the series. Blood oxytocin was assayed on the lactating guinea-pig mammary gland. Forty series of serial blood samples were also collected from 12 goats during hand-milking over the first 6 weeks of lactation and the transient appearance of oxytocin (5–160 μu./ml plasma) was observed in 25 of these.
The results indicated that: (1) oxytocin may be released at any time during the suckling or milking process; (2) in only 16% of experiments where oxytocin was released and 5·6% of all experiments investigated could a conditioned release of oxytocin be induced in goats before suckling and in no case before hand-milking despite a vigorous and prolonged conditioning period; (3) there is a large degree of variability in the pattern of oxytocin release between animals and between individual suckling and milking episodes in the same animal; (4) suckling and hand-milking are equally effective in causing the release of oxytocin; (5) stimuli arising during various stages of the suckling and hand-milking routines may be assigned a figure indicative of the relative effectiveness of these stimuli in terms of percentage probability in causing oxytocin release; (6) there is a greater probability of oxytocin release occurring before suckling than before hand-milking; (7) there is a very marked similarity in the pattern of oxytocin release both during and after teat stimulation in response to suckling and milking stimuli; (8) there is a greater probability of oxytocin being released in response to hand-milking during early lactation than during late lactation; (9) the milk-ejection reflex in the goat does not appear to be important for the achievement of normal milk yields during suckling or hand-milking.