bluuebunny/crossref_metadata_2025_split huggingface dataset:
PREFERENTIAL RELEASE OF OXYTOCIN FROM THE NEUROHYPOPHYSIS AFTER ELECTRICAL STIMULATION OF THE AFFERENT PATH OF THE MILK-EJECTION REFLEX IN THE BRAIN OF THE GUINEA-PIG
Authors: TINDAL J. S. , KNAGGS G. S. , TURVEY A. 
Published: December 2008

SUMMARY
Discrete portions of the afferent path of the milk-ejection reflex have been explored in the brain of the lactating guinea-pig. Both intramammary pressure and arterial blood pressure were recorded to detect release of oxytocin and vasopressin. It was found that the milk-ejection responses which occurred after electrical stimulation of the pathway in the midbrain and hypothalamus were caused by the release of oxytocin without detectable release of vasopressin.
A mixture of oxytocin and vasopressin, in the ratio of approximately 3:1, was released only after electrical stimulation of the rostral tuberal region of the hypothalamus adjacent to the pituitary stalk.
It is concluded that the afferent path in the brain of the guinea-pig studied is concerned with the preferential release of oxytocin from the neurohypophysis and that it is the pathway of the milk-ejection reflex.
HISTOCHEMICAL OBSERVATIONS ON THE GRANULOSA AND THECA INTERNA DURING FOLLICULAR DEVELOPMENT AND CORPUS LUTEUM FORMATION AND REGRESSION IN THE AMERICAN OPOSSUM
Authors: GURAYA S. S. 
Published: December 2008

SUMMARY
A study has been made of the histochemical changes which occur during follicular growth and formation and regression of the corpus luteum in the ovary of the American opossum. The granulosa cells show abundant cytoplasmic RNA. Some lipid bodies consisting of phospholipids are sparsely distributed among the granulosa cells. After ovulation, the granulosa cells undergo 'luteinization' to form the large luteal cells. The most striking histochemical change involved in the differentiation (or luteinization) of the granulosa follicle cell into a luteal cell is the development of abundant diffuse lipoproteins throughout the cytoplasm. Fine lipid granules consisting of phospholipids are also formed in the cytoplasm of luteal cells.
The stromal elements of the theca interna, which contain some sparsely scattered phospholipid granules, do not show any histochemical change during corpus luteum formation.
With the regression of luteal cells, coarse lipid granules consisting of cholesterol and cholesterol esters, triglycerides and some phospholipids accumulate abundantly in the cytoplasm. Some of these regressing luteal cells continue to persist in the ovarian stroma for some time.
DISTRIBUTION OF HYDROXYSTEROID DEHYDROGENASES IN THE PLACENTA OF THE PIG
Authors: CHRISTIE G. A. 
Published: December 2008

SUMMARY
The presence of hydroxysteroid dehydrogenases in the pig placenta and associated uterine structures is described between 26 days of gestation and term.
Activity with androsterone, aetiocholanolone, DHA, pregnenolone, 17α-hydroxypregnenolone, 3β-hydroxy-5β-androstan-17-one, cortisol, 3β,16β-dihydroxyandrost-5-ene 3-methyl-ether, 3,16β-dihydroxyoestra-1,3,5(10)-triene 3-methyl-ether, oestradiol-17β, and 20β-hydroxyprogesterone in the trophoblast increased in mid-pregnancy, and thereafter decreased towards term, except with androsterone, cortisol, 3β,16β-dihydroxyandrost-5-ene 3-methyl-ether, 3,16β-dihydroxyoestra-1,3,5(10)-triene 3-methyl-ether and oestradiol whose increased level of activity persisted. No activity was found in the trophoblast with 1 1β-hydroxyandrostenedione, 3β-hydroxyandrost-5-en-16-one 3-methyl-ether, 17α-oestradiol, testosterone, or 20α-hydroxyprogesterone. Activity in the trophoblast of the areolae was consistently absent or greatly decreased.
In the maternal epithelium, intense activity with oestradiol-17β, and testosterone as substrates (but no others) was observed early in pregnancy, but decreased markedly later. Activity was consistently higher in the epithelium related to the opening of the areolae. No other uterine or foetal structures gave a positive reaction.
Some attempt is made to correlate the presence of the enzymes with their function, with biochemical findings regarding isolation of steroids from the placenta, and with the effects of ovariectomy on pregnancy in the pig.
REPLETION OF VASOPRESSIN AND OXYTOCIN IN THE POSTERIOR LOBE OF THE PITUITARY GLAND OF THE RAT
Authors: YOUNG T. K. , VAN DYKE H. B. 
Published: December 2008

SUMMARY
Rats deprived of drinking water for 7 days showed a striking depletion of neurohypophysial hormones from the posterior lobe of the pituitary gland. The average daily depletion rate was estimated to be 93 m-u. for vasopressin and 97 m-u. for oxytocin. When rats were allowed free access to water, dehydration was rapidly corrected as shown by normal haematocrit values and plasma osmolarities. Repletion of neurohypophysial hormones, rapid in the first 24 hr., continued gradually thereafter. The mean calculated repletion rate was 41 m-u./day for vasopressin and 42 m-u./day for oxytocin. Repletion was completed about 14 days after rehydration.
INDUCTION OF NIDATION IN HYPOPHYSECTOMIZED PROGESTERONE-TREATED PREGNANT RATS BY NON-SPECIFIC FACTORS
Authors: VARAVUDHI P. 
Published: December 2008

SUMMARY
Nidation may be induced on the evening of L3 in hypophysectomized pregnant rats by subcutaneous injection of proteolytic enzymes, protein precipitants, and by acidic extracts of rat hypothalamus, cerebral cortex, heart, liver and spleen. With the exception of the protein precipitants, these materials apparently stimulated the ovary to release sufficient oestrogen for nidation provided that exogenous progesterone was available. Similarly, implantation could be induced (on L9) by extracts of adenohypophysis, hypothalamus, cerebral cortex or trypsin in hypophysectomized pregnant rats in delayed nidation. However, a single injection of blood serum from male or female rat donors was ineffective. The assumption is made that specific gonadotrophins from the pituitary are not the only factors able to cause release of oestrogen from the ovary.
PROGESTERONE CONCENTRATIONS IN THE ARTERIAL PLASMA OF GUINEA-PIGS DURING THE OESTROUS CYCLE
Authors: FEDER H. H. , RESKO J. A. , GOY R. W. 
Published: December 2008

SUMMARY
The quantities of circulating progesterone and its 20-dihydro metabolites in cyclic female guinea-pigs were estimated by gas chromatography with electron capture detection. Forty-four animals were divided into 13 groups of approximately equal size according to stage of the oestrous cycle. The day on which a lordosis response could be elicited was designated Day 0 of the cycle. In the first few hours of sexual receptivity on Day 0 progesterone levels were 0·36 ± 0·07 μg./100 ml. arterial plasma. The ovaries were pre-ovulatory at this stage. After 5 to 12 hr. of behavioural receptivity progesterone levels dropped to 0·04 ± 0·01 μg./100 ml. plasma, and at the termination of receptivity (just after ovulation) progesterone was almost completely undetectable.
The concentration of progesterone increased gradually after ovulation reaching a peak about Day 9 (0·30 ± 0·05 μg./100 ml. plasma) and then fell to undetectable levels by Day 15. The 20-dihydro metabolites of progesterone were not present in significant quantities at any stage of the cycle.
It is concluded that in guinea-pigs a surge of progesterone occurs approximately 8 to 12 hr. before ovulation and coincides with the onset of oestrous behaviour. The plasma concentration of progesterone at this pre-ovulatory stage is at least as high as that measured at any point during the luteal phase.
DISAPPEARANCE OF HISTOCHEMICALLY-DEMONSTRABLE ADENOSINE TRIPHOSPHATASE AND OF PAS-REACTIVE BASEMENT MEMBRANES IN BLOOD VESSELS IN THE DECIDUA DURING OVUM IMPLANTATION IN MICE
Authors: HALL KATHLEEN 
Published: December 2008

SUMMARY
Histochemical studies were made of the endometrial blood vessels before and after normal implantation of blastocysts in intact mice and delayed implantation in pregnant, spayed, hormone-treated mice.
Adenosine triphosphatase (ATPase) activity was investigated by the calcium method of Padykula and Herman and the lead method of Wachstein and Meisel, controlled by inclusion of inhibitors and by substitution of other substrates. Paraffin sections were subjected to the periodic acid-Schiff (PAS) technique.
In the endothelium of endometrial blood vessels intense ATPase staining occurred on days 2 to 5 in intact mice and until at least day 9 in spayed mice injected with progesterone alone (no implantation), and in the non-decidual areas after normal (day 6) or induced (days 7–9) implantation. The reaction appeared to be localized in the endothelial plasma membranes, mainly in the basal membrane. The basement membranes of these vessels reacted strongly with PAS.
Within decidual tissue at the implantation sites in both intact and spayed mice ATPase activity was completely absent from all blood vessels. The basement membranes of these vessels gave no reaction with PAS. There was close correlation in distribution and time of appearance between absence of ATPase activity and differentiation of alkaline phosphatase-reactive decidual cells.
The specificity of the vascular reaction with ATP is considered in the light of its behaviour towards enzyme inhibitors and other substrates, and the significance of its disappearance in decidual blood vessels is discussed.
A COMPARISON OF THE METABOLISM IN VITRO OF [7α-3H] DEHYDROEPIANDROSTERONE SULPHATE AND [4-14C] PREGNENOLONE BY TISSUE FROM A HILUS CELL TUMOUR OF THE OVARY
Authors: FAHMY D. , GRIFFITHS K. , TURNBULL A. C. , SYMINGTON T. 
Published: December 2008

SUMMARY
Tissue from a hilus cell tumour of an ovary removed from a 58-yr.-old virilized woman was incubated simultaneously with [7α-3H]dehydroepiandrosterone sulphate (DHA sulphate) and [4-14C]pregnenolone. The tissue was chopped and incubated in Krebs-Ringer bicarbonate glucose medium without the addition of cofactors. Both steroids were efficiently metabolized by the tissue; 78·5 and 1·2% of the pregnenolone was converted to androstenedione and testosterone respectively, whereas 34·6% of the incubated DHA sulphate was isolated in the carrier DHA, 41·4% in the androstenedione and 0·5% in the testosterone.
RECOVERY FROM X-RAY IRRADIATION INJURY DURING DELAYED IMPLANTATION IN THE RAT
Authors: HOOVERMAN LOIS L. , MEYER R. K. , WOLF R. C. 
Published: December 2008

SUMMARY
Whole body X-ray irradiation was administered to rats during experimentally delayed implantation. The effects of a short (1-day) and a long (9-day) interval between irradiation and the induction of implantation were studied.
When one day intervened between irradiation and the induction of implantation, foetal survival decreased with each increase in dose (200–500 r.) and the weights of surviving foetuses were significantly lower than those of the non-irradiated controls.
Foetal survival in rats with a 9-day interval between irradiation and the induction of implantation was not significantly different from that of the controls. Foetal weight was lower than that of non-irradiated controls but greater than that of rats with only a 1-day interval.
It is concluded that the 9-day interval between irradiation and the induction of implantation allows time for repair of irradiation injury.
CELLULAR BEHAVIOUR OF THE VAGINAL EPITHELIUM TREATED WITH TESTOSTERONE PROPIONATE ALONE AND IN COMBINATION WITH DIETHYLSTILBOESTROL
Authors: LADINSKY J. L. , GRUCHOW H. W. , PECKHAM B. M. 
Published: December 2008

SUMMARY
The kinetics of the vaginal epithelium and changes in vaginal epithelial thickness of ovariectomized female rats under the influence of various doses of testosterone propionate alone and in combination with 0·1 μg. diethylstilboestrol were studied. Testosterone propionate alone in the range of doses used had no effect on cell proliferation, yet the thickness of the vaginal epithelium increased due to mucification resulting in increased cell size. Testosterone propionate in the presence of 0·1 μg. diethylstilboestrol completely antagonized the proliferative effect of the oestrogen. However, the changes of the vaginal epithelial thickness in response to the oestrogen—androgen combination showed no evidence of antagonism, the effects being additive with a synergistic response within the narrow dose response range of 50 to 100 μg. testosterone propionate in the presence of 0·1 μg. diethylstilboestrol. The thickness determinations showed that oestrogen was not inhibited by testosterone, but sustained its action by a mucification effect.
THE INCORPORATION OF TRITIATED URIDINE IN THE UTERUS AND VAGINA OF THE MOUSE DURING EARLY PREGNANCY
Authors: MILLER B. G. , OWEN W. H. , EMMENS C. W. 
Published: December 2008

SUMMARY
In the uterus of pregnant mice an increase in uptake of tritiated uridine occurs between days 2 and 3 of pregnancy, followed by a further increase from day 4 onwards. Uridine uptake changes in the same manner in pseudopregnant mice up to day 4, but thereafter declines to a minimum at day 6. The non-pregnant horn of the unilaterally pregnant mouse shows the same changes as the uterus of the pseudopregnant mouse. The results suggest that implantation occurs during a period of declining ovarian stimulation of the uterus and that the increased uptake of uridine in pregnant mice is stimulated locally by implantation.
ASSESSMENT OF OVARIAN SECRETION OF OESTROGEN DURING THE OESTROUS CYCLE BY THE USE OF BIOLOGICAL CRITERIA
Authors: BARNEA AYALLA , GERSHONOWITZ T. , SHELESNYAK M. C. 
Published: December 2008

SUMMARY
Adult female rats were ovariectomized at various stages of the oestrous cycle; configuration of the vaginal smear and uterine wet weights were determined at various time-intervals after operation.
The results suggested that oestrogen secretion is lowest at oestrus and metoestrus, increases gradually during dioestrus, and continues until the evening of pro-oestrus; progesterone is secreted on the afternoon and evening of pro-oestrus.
THE ROLE OF PROGESTERONE IN THE BIOSYNTHESIS OF CORTISOL IN HUMAN ADRENAL TISSUE
Authors: CAMERON E. H. D. , BEYNON M. A. , GRIFFITHS K. 
Published: December 2008

SUMMARY
The ability of cells from the zona fasciculata and the zona reticularis of the human adrenal cortex to transform labelled pregnenolone and progesterone to cortisol in vitro was investigated. Examination of the 3H:14C ratios of 16α-hydroxyprogesterone, 17α-hydroxyprogesterone, 11-deoxycorticosterone and cortisol formed during incubations in vitro suggested that the role of progesterone in the transformation of pregnenolone to cortisol might be a relatively minor one.
An attempt was subsequently made to estimate the relative importance of the biosynthetic pathway to cortisol by way of progesterone in hyperplastic adrenal tissue by a mathematical approach.
CHANGES IN THE SIALIC ACID CONTENT OF THE ACCESSORY GLANDS OF THE MALE RAT
Authors: RAJALAKSHMI M. , PRASAD M. R. N. 
Published: December 2008

SUMMARY
Sialic acid is secreted by the testis, epididymis, ductus deferens and Cowper's gland of the male albino rat. Castration results in a considerable reduction in the sialic acid content of these organs. Androgen administration to castrated rats elevates the sialic acid levels in Cowper's gland to control values, while that of the other organs is only partially restored. This is probably due to the presence of spermatozoa in the epididymis in the control animals and is supported by the decreased values of sialic acid in animals with ligatures. The physiological integrity of the epididymal canal and Cowper's gland is thus dependent on the circulating levels of androgen.
THE LOCALIZATION OF ADRENALINE-RICH MEDULLARY CHROMAFFIN CELLS ADJACENT TO THE ADRENAL CORTEX
Authors: RUBIN R. P. , COHEN M. S. , HARMAN S. M. , ROER E. M. 
Published: December 2008

SUMMARY
The residual catecholamine content of the cat adrenal gland after the removal of much of the medulla contained a significantly higher percentage of adrenaline than that of the excised medulla. Fluorescent and phase microscopy showed that in these glands a layer of medullary tissue adjacent to the cortex still remained. The high concentration of adrenaline in chromaffin cells nearest to cortical tissue provides further evidence for the theory that the adrenal cortex acts to facilitate the formation of adrenaline from noradrenaline in the medulla.
PROGESTERONE LEVELS IN THE ARTERIAL PLASMA OF PRE-OVULATORY AND OVARIECTOMIZED RATS
Authors: FEDER H. H. , RESKO J. A. , GOY R. W. 
Published: December 2008

SUMMARY
The concentrations of progesterone and 20α-hydroxypregn-4-en-3-one in the systemic circulation of 5-day cyclic rats were estimated by gas—liquid chromatography with electron capture detection. Behavioural receptivity (lordosis) was the criterion taken to mark the start of the oestrous cycle. Progesterone levels were highest during the pre-ovulatory period when lordosis was being displayed (3·11 ± 0·41 μg./100 ml. plasma). Several hours later, at the end of the receptive period, the progesterone concentration had declined to 1·18 ± 0·24 μg./100 ml. plasma. Except for a small mid-cycle increase the concentrations throughout the remainder of the oestrous cycle remained below this level until the morning of expected behavioural receptivity, when they rose to 2·14 ± 1·15 μg./100 ml. plasma. The concentration of 20α-hydroxypregn-4-en-3-one did not vary significantly with the cycle.
After ovariectomy, the 20α-dihydro metabolite disappeared from the circulation within 48 hr. Progesterone, however, was measurable in the plasma even 25 days after ovariectomy. After ovariectomy and adrenalectomy, progesterone was undetectable within 8 hr. It was concluded that under anaesthesia and surgical stress the rat adrenal may release significant amounts of progesterone.
OVARIAN ACTIVITY IN TESTOSTERONE-STERILIZED FEMALE RATS UNDER CONTINUOUS ILLUMINATION
Authors: COLOMBO J. A. 
Published: December 2008

SUMMARY
Four-day-old female rats were injected subcutaneously with 1·25 mg. testosterone propionate. Some of these rats were divided into two groups when 10–13 days old and others when mature. One group of each age was placed under periodic illumination (p.i.) and the others under continuous illumination (c.i.). Animals undergoing c.i. when immature showed no significant differences concerning the appearance of first oestrus or ovarian or uterine relative weights when compared with the p.i. group on the 60th day of life. Similarly, no differences could be observed in ovarian and uterine absolute and relative weights between the c.i. and the p.i. groups during adult life. The possible mechanisms involved in this phenomenon are discussed.
A RAPID METHOD FOR ESTIMATING OESTROGENS IN URINE USING A SEMI-AUTOMATIC EXTRACTOR
Authors: BROWN J. B. , MacLEOD S. C. , MACNAUGHTAN CAROLINE , SMITH MARGERY A. , SMYTH BARBARA 
Published: December 2008

SUMMARY
A semi-automatic extractor was developed which processes 12 urines at a time to a stage where 'total' oestrogens can be measured by colorimetry using the Kober reaction (late pregnancy urines) or by fluorimetry using the Kober—Ittrich procedure (non-pregnancy and early pregnancy urines). One worker can complete 12 analyses in 3½ hr. or 24–36 in a working day. The results obtained at oestrogen levels above 1 mg./24-hr. urine were the same as those obtained by a method specific for oestriol. The results obtained from non-pregnancy urines were compared with the sums of oestriol, oestrone and oestradiol obtained by the method of Brown (1955). The mean ratio (± s.d.) of the two values was 1·22 ± 0·31. The comparisons indicated that the short procedure was the more reliable method at levels below 5 μg./24-hr. urine. Values for normal subjects are given. The methods appear to be entirely suitable for assessing oestrogen production by the ovaries, testes, adrenals and placenta.
ISOLATION AND IDENTIFICATION OF 20α-HYDROXY-5β-PREGNAN-3-ONE FROM URINE OF PREGNANT WOMEN: GAS CHROMATOGRAPHY OF PREGNANOLONES AND PREGNANEDIOLS
Authors: van der MOLEN H. J. , GROEN D. , ROMMERTS F. F. G. , VAN DER MAAS J. H. 
Published: December 2008

SUMMARY
20α-Hydroxy-5β-pregnan-3-one was isolated from the extracts of enzyme or acid-hydrolysed pregnancy urine using various chromatographic procedures including gas chromatography Identification of the steroid was based upon: (1) behaviour of the free and acetylated compound, and of the products, following stereospecific enzymatic oxidations, during gas chromatography on different stationary phases, and (2) infrared spectrometry of the compound collected after gas chromatography. The gas-chromatographic behaviour of the isomers of 3-hydroxypregnan-20-one, 20-hydroxypregnan3-one and pregnane-3,20-diol and their acetates is reported.
REGULATION AND DISTRIBUTION OF PLASMA CALCIUM AND INORGANIC PHOSPHATE IN THE EUROPEAN EEL (ANGUILLA ANGUILLA L.)
Authors: CHAN D. K. O. , JONES I. CHESTER 
Published: December 2008

SUMMARY
The amounts of ionized, complexed and protein-bound calcium and total inorganic phosphate were measured in the plasma of the eel. Groups comprised freshwater, seawater and distilled water eels; treatment with corticotrophin (ACTH), cortisol, aldosterone or oestrogen; adrenalectomized and hypophysectomized eels and those with the corpuscles of Stannius removed. In the intact animal, the amounts of ultrafiltrable and ionic calcium and inorganic phosphate in the plasma were very constant despite wide variation in the electrolyte composition of the external medium. In the freshwater eel, 1 week after removal of the corpuscles of Stannius, there was a rise in the level of ultrafiltrable calcium and a decline in that of inorganic phosphate. At 3 weeks after operation, although total calcium concentration remained elevated, ultrafiltrable and ionic calcium concentrations returned to control values. Adrenalectomy and hypophysectomy of the freshwater eel resulted in a decline in total calcium concentration with change in the levels of ultrafiltrable calcium or inorganic phosphate. In the seawater eel, adrenalectomy or removal of the corpuscles of Stannius resulted in an increase in total and ultrafiltrable calcium concentrations. Injection of ACTH, cortisol or aldosterone did not affect calcium concentrations but gave a slight decline in inorganic phosphate levels. Injection of oestrogen increased total calcium concentration without affecting ultrafiltrable or ionic calcium concentrations. The relationship of the amounts of ultrafiltrable calcium and inorganic phosphate to the solubility product [ultrafiltrable calcium] × [phosphate] is discussed and attention drawn to the importance of protein-binding in calcium homeostasis.
THE EFFECT OF TESTOSTERONE OR OESTRADIOL UPON THE SEXUAL AND ASSOCIATED BEHAVIOUR OF THE ADULT FEMALE RHESUS MONKEY
Authors: TRIMBLE M. R. , HERBERT J. 
Published: December 2008

SUMMARY
The effect on sexual behaviour of testosterone propionate (1, 5 or 25 mg./day) or oestradiol monobenzoate (50 μg./day) administered to ovariectomized female rhesus monkeys was studied in the laboratory in six females and three males. One milligram testosterone increased the frequency with which the females 'presented' to the males—that is, invited them to mount. But the proportion of these presentations effective in stimulating the male, and the males' sexual activity, remained low. Oestradiol had a similar, but lesser, effect on the females' behaviour but resulted in marked stimulation of the males' mounting activity, and increased the sexual response of the males to the females' sexual presentations. Larger doses of testosterone had a decreasing effect upon the females' presentations, but increased their aggression towards the males; some females became progressively less receptive to the males' attempts to mount. The effects of these hormones on behaviour and on the females' vaginal smears, sexual skins and clitorides were compared. These studies did not finally establish the site of action of administered hormone, but suggested that testosterone may have stimulated the females' receptivity by an action mainly on their central nervous systems, whereas oestrogen increased their sexual attractiveness to the male principally by an action on their genitalia.