bluuebunny/crossref_metadata_2025_split huggingface dataset:
A COMPARISON OF THE EFFECTS OF ADRENALECTOMY AND OF CHLOROTHIAZIDE IN EXPERIMENTAL DIABETES INSIPIDUS
Authors: KENNEDY G. C. , CRAWFORD J. D. 
Published: December 2008

SUMMARY
Chlorothiazide and its analogues had a marked antidiuretic action in diabetes insipidus; the effect appeared to be independent of that of antidiuretic hormone. In a series of rats which had been treated with these saluretic drugs, subsequent adrenalectomy had a similar antidiuretic effect. Chlorothiazide produced little or no further antidiuresis in these adrenalectomized animals, but it prevented the restoration of polyuria which otherwise followed the administration of adrenal steroids. It is suggested that the distal part of the renal tubule where osmotically free water is released is a site of action common to chlorothiazide and corticoids.
STEROID CONCENTRATIONS IN THE FOLLICULAR FLUID OF MARES AT VARIOUS STAGES OF THE REPRODUCTIVE CYCLE
Authors: SHORT R. V. 
Published: December 2008

SUMMARY
The following steroids were estimated in each of twelve samples of follicular fluid collected from oestrous, luteal-stage and pregnant mares: progesterone, 17α-hydroxyprogesterone, androstenedione, epitestosterone, 19-norandrostenedione, oestrone, oestradiol-17β and 6 'α'-hydroxyoestradiol-17β. In ten of the samples oestradiol-17β was the major steroid present. In one sample taken from a pregnant animal oestradiol-17β could not be detected at all, and in its place large amounts of progesterone and 20α-hydroxypregn-4-en-3-one were found.
The larger follicles tended to have the higher steroid concentrations. In this series, there was no significant difference in concentration between oestrous and luteal-phase animals with respect to any of the steroids measured (P > 0·05); the reasons for this are discussed. It is concluded that the gonadotrophic hormones do not act by influencing any rate-limiting reaction in the conversion of progesterone to oestrogens.
Since the ratios of the various steroids seem to differ greatly between follicular fluid and luteal tissue, it is postulated that cell type may be the chief discriminant of the secretory activity of the ovary.
THE MAMMARY GLANDS OF SENILE NULLIPAROUS AND MULTIPAROUS RATS
Authors: HOWELL J. S. , MANDL ANITA M. 
Published: December 2008

SUMMARY
Sixty-nine nulliparous rats aged 607–1156 days and forty-six multiparous rats aged 614–1071 days were examined.
The incidence of mammary tumours, hyperplasia of the mammary glands, enlargement of the pituitary, and occurrence of excessively large corpora lutea, were strikingly higher in the virgin than in the breeding animals. The nulliparae also tended to be heavier, and to possess larger ovaries and adrenal glands than did the parous animals.
CYCLICAL CHANGES IN THE VAGINAL SMEARS OF SENILE NULLIPAROUS AND MULTIPAROUS RATS
Authors: MANDL ANITA M. 
Published: December 2008

SUMMARY
The pattern of the vaginal smear of senile nulliparous rats can be subdivided into three categories: (1) prolonged cycles characterized by long phases of vaginal cornification; (2) prolonged cycles associated with long dioestrous periods and occasional mucification; and (3) sporadic mucification and appearance of epithelial cells which follow so irregular a course that no cycles can be detected. The first type of pattern is associated with absence of corpora lutea, and a high incidence of pituitary enlargement and mammary fibroadenomata. The second and third types are associated with the presence of excessively large corpora lutea, and a lower incidence of pituitary enlargement and fibroadenomata.
In contrast, the majority of senile multiparae show normal or only slightly atypical oestrous cycles. The incidence of excessively large corpora lutea, pituitary enlargement and mammary fibroadenomata is markedly lower than in the nulliparae.
DOES PROLACTIN INDUCE INCUBATION BEHAVIOUR IN THE RING DOVE?
Authors: LEHRMAN D. S. , BRODY P. 
Published: December 2008

SUMMARY
Prolactin, injected into ring doves with previous breeding experience, is relatively ineffective, compared with progesterone, in inducing incubation behaviour. Even at dosage levels inducing full crop growth, only 40% of the individuals tested, coming from 65% of the pairs tested, sat on eggs. This is significantly less than the response to progesterone, which induces incubation behaviour in 70% of the individuals, representing 95–100% of the pairs tested. At smaller dosage levels of prolactin, it was possible to cause significant increases in crop weight by injecting the hormone in amounts having no effect whatever on incubation behaviour. Since incubation normally starts well before the onset of crop growth, it appears that incubation normally begins when blood prolactin levels are too low to induce it. We therefore conclude that prolactin is normally not principally responsible for the initiation of incubation behaviour, at least in the ring dove.
THE ONTOGENY OF INSULIN SECRETION IN THE CHICK EMBRYO
Authors: GRILLO T. ADESANYA I. 
Published: December 2008

SUMMARY
Histological examination (azan method) of the islets of Langerhans of the chick embryo showed that β cells were present on the 11–12th day of incubation, but it was difficult to be certain that granules were present in the cells on those days. An occasional granulated β cell could be seen on the 12th day but granulation became general by the 16th day.
Histochemical tests (by the Barrnett & Seligman technique) indicated the presence of protein-bound sulphydryl groups in the β cells from the 14th day of incubation onwards.
Bioassays of the pancreas by the rat diaphragm method showed that insulin was, in fact, present from the 12th day of incubation onwards.
There is no evidence for the presence of insulin in egg yolk, since yolk extracts did not enhance the glucose uptake of rat diaphragm.
Alloxan did not inhibit the development of β cells in the pancreas of chick embryos.
THE MAINTENANCE OF LACTATION IN THE RAT AFTER HYPOPHYSIAL ANTERIOR LOBECTOMY DURING PREGNANCY
Authors: COWIE A. T. , TINDAL J. S. 
Published: December 2008

SUMMARY
Experiments to determine the pituitary hormones necessary for the maintenance of lactation in the rat in the absence of either the anterior lobe of the pituitary or the entire pituitary are described.
The anterior pituitary or the whole of the pituitary was removed on the 12th day of pregnancy and prolactin (25 i.u. twice daily) plus adrenocorticotrophic hormone (ACTH) (2 i.u./day) was given to the animals from parturition to the 10th day of lactation inclusive. The lactational performances of the two operated groups of rats, as judged by the litter-growth indices, were 53% (anterior lobectomy) and 43% (hypophysectomy) of normal.
The milk-ejection reflex was completely restored in the anterior-lobectomized rats by the time of parturition, but the hypophysectomized rats required a further 2 days before milk ejection appeared to be normal.
Our experiments confirm that prolactin and ACTH are two important factors in the maintenance of milk secretion in the rat. Since only partial restoration was achieved, however, it is clear that other factors, presumably of anterior-pituitary origin, are required for the full restoration of lactation.
Δ5 3β-HYDROXY STEROIDS IN THE FOLLICULAR FLUID OF THE MARE
Authors: SHORT R. V. 
Published: December 2008

SUMMARY
A pool of 500 ml. normal equine follicular fluid was examined for the presence of Δ5 3β-hydroxy steroids. Neither pregnenolone nor 17α-hydroxypregnenolone could be detected (< 1 μg./l.), but there appeared to be a small amount of dehydroepiandrosterone (DHA) present (8 μg./l.). These findings suggest that in the Graafian follicle of the mare the conversion of pregnenolone to progesterone normally proceeds fairly rapidly, and the pregnenolone → 17α-hydroxypregnenolone → DHA → androstenedione pathway is probably of minor importance.
THE BLOCKING BY SPIROLACTONES OF THE ACTIONS OF ALDOSTERONE AND CORTISOL UPON THE HUMAN KIDNEY
Authors: MILLS J. N. , THOMAS S. , WILLIAMSON K. S. 
Published: December 2008

SUMMARY
The blocking effect of spironolactone ('Aldactone', Searle) has been tested against 100 mg. cortisol, and 0·25 mg. d-aldosterone, given intravenously. The sodium retention induced by either steroid is roughly halved by either a 300 or a 600 mg. dose of spironolactone. The high potassium excretion induced by cortisol is little if at all affected by spironolactone; the acute kaliuretic action of aldosterone is too small and inconstant to permit a clear assessment of blocking action. The implications of the apparent dissociation of the effects of cortisol upon sodium and upon potassium excretion are discussed.
CENTRAL ACTIVATION OF THE SYMPATHETICO-ADRENAL SYSTEM BY HYPOXIA AND HYPERCAPNIA
Authors: CROSS B. A. , SILVER I. A. 
Published: December 2008

SUMMARY
In rabbits under urethane anaesthesia sympathetico-adrenal vasoconstrictor activity was monitored by the reduction of oxygen tension (measured polarographically with needle electrodes) in the testis and lactating mammary gland, and by the inhibitory effect on milk ejection. Electrical stimulation of the dorsal, lateral and posterior hypothalamus evoked a sympathetic response in these organs, characterized by a rapid nervous effect and secondary humoral effect which outlasted the stimulus, resembled the response to intravenous adrenaline, and was abolished by removal of both adrenal glands. Hypoxia produced by making the animals inhale nitrous oxide or nitrogen for 15–30 sec. and hypercapnia induced by inhalation of a mixture of 80% CO2 and 20% O2 for 5–15 sec. both induced a sympathetic discharge similar to that resulting from hypothalamic stimulation. Hypercapnia was a notably more potent stimulus than hypoxia. The effects were reversibly blocked by thoraco-lumbar spinal anaesthesia. Placement of discrete bilateral lesions in the septum, hippocampus and medial thalamus did not impair the sympathetic activation elicited by hypercapnia. Hypothalamic lesions, on the other hand, often reduced and occasionally prevented the central sympathetic discharge. The possible role of the hypothalamus in cardiovascular regulation is discussed in the light of these findings.
THYROID FUNCTION IN RATS SELECTIVELY BRED FOR EMOTIONAL ELIMINATION
Authors: FEUER G. , BROADHURST P. L. 
Published: December 2008

SUMMARY
1. The amount and distribution of thyroid hormones have been studied in the blood and thyroid gland of rats of both sexes from the Maudsley Reactive and Non-reactive strains, selectively bred for emotional defecation.
2. The amount of thyroid hormones in the thyroid gland was significantly lower in the animals from the high-defecating strain than in those from the low-defecating strain.
3. The quantity of protein-bound iodine in the serum was significantly lower in the high-defecating strain than in the low-defecating strain.
4. From the thyroid gland and from the serum the thyroid hormones were extracted with butanol and quantitatively determined. The ratio of the thyroid hormones was different in the two strains, thyroxine being lower and triiodothyronine (with other iodine-containing compounds) higher in the high-defecating strain.
SERUM HORMONAL IODINE VALUES DURING AND FOLLOWING PREGNANCY IN THE MONKEY (MACACA MULATTA)
Authors: KERR G. R. 
Published: December 2008

SUMMARY
1. Serial butanol extractable iodine (BEI) determinations were performed on the sera of fifty-one healthy pregnant and non-pregnant female monkeys (Macaca mulatta) over a period of 18 consecutive months.
2. The mean serum BEI value for non-pregnant monkeys was 3·5 ± 0·8 μg./100 ml. Monthly variations from the mean were not significant. Each animal demonstrated serial BEI values about a mean specific for that animal.
3. An apparent rise in BEI values was observed 22–35 days following conception and continued during the first 120 days of pregnancy; thereafter, values tended to remain level until shortly before term when they dropped slightly. A transient elevation was frequently observed during the first 5 days following delivery, after which the values dropped rapidly and reached control levels by 35 days post partum.
THE EFFECT OF OVARIECTOMY ON RABBIT BLASTOCYSTS
Authors: LUTWAK-MANN CECILIA , HAY MARY F. , ADAMS C. E. 
Published: December 2008

SUMMARY
The behaviour of rabbit blastocysts and their uterine environment after ovariectomy was studied; the experimental period after ovariectomy varied from 17 to 26 hr. Most of the experiments were concerned with blastocysts recovered from rabbits spayed at 6 days; a few relate to embryos from animals spayed on day 5 or 7 of gestation.
Ovariectomy resulted in variable, often considerable, embryonic loss. Following bilateral ovariectomy at 6–6½ days, implantation on day 7 was completely prevented; those blastocysts which survived showed evidence of expansion and differentiation during the interval after ovariectomy. This provided an opportunity (1) to assess the stage of development, and mitotic activity, as well as certain biochemical characteristics, in embryos surviving ovariectomy, and (2) to use the free-lying 7-day-old blastocysts for culture experiments.
It was found that mitotic activity went on in blastocysts after ovariectomy. Upon transfer to suitable culture media the unimplanted 7-day-old blastocysts continued to grow and differentiate, the most advanced stage observed at the end of a 24 hr. period of incubation in vitro being the development of blood islands, primitive groove, and head process.
The fresh weight, and the content of bicarbonate and glucose of the 7-day-old unimplanted blastocysts differed little from those of normally implanted blastocysts of the same age; their content of lactate, however, was distinctly lower.
Carbonic anhydrase activity after spaying was fully maintained in the endometrium which showed little involutional change either on gross or on microscopical examination.
THE METABOLISM OF [4-14C]CORTISOL IN A PATIENT WITH CUSHING'S SYNDROME
Authors: GRAY C. H. , GREENAWAY J. M. , HOLNESS N. J. , SHAW D. A. 
Published: December 2008

SUMMARY
The metabolism of [4-14C]cortisol in a patient with Cushing's syndrome has been studied by the isolation, identification and measurement of the specific radioactivities of the major metabolites.
The results show that the metabolism of cortisol was not abnormal in the aspects studied. The biological half-lives of cortisol and of the tetrahydrocorticosteroid metabolites were found to be normal. Data obtained on excretion rates of metabolites indicated that the metabolic pathways of cortisol were normal. There was no evidence for an increased conversion of cortisol to 6β-hydroxycortisol when the excretion of the latter was expressed as a fraction of the cortisol production.
The overall pattern was one of an abnormally high secretion of cortisol by the adrenals, resulting in a proportionally high excretion of tetrahydrocortisone, tetrahydrocortisols, cortolones, cortols, 11-oxygenated 17-oxosteroids, 6β-hydroxycortisol, cortisone and cortisol. Apart from an increased ratio of 11β-hydroxy-metabolites to 11-oxo-metabolites, each metabolite, expressed as a fraction of the cortisol secreted, was excreted in a normal proportion.
Hence, in spite of the grossly elevated cortisol secretion rate, the major pathways available for cortisol metabolism were not overloaded and there was no evidence of increased metabolism via minor pathways.
Evidence for an increased secretion of corticosterone by the adrenals was obtained by the isolation of abnormal amounts of tetrahydrocorticosterone.
DETERMINATION OF OESTROGENS IN THE FAECES OF SHEEP
Authors: WRIGHT A. A. 
Published: December 2008

SUMMARY
1. Attempts have been made to estimate oestrogens in residues from sheep faeces using two methods of purification.
2. Low recoveries of oestrogens added to the faeces were recorded with both methods.
3. Some batches of faeces contain contaminants which remain in the final fractions and interfere markedly in colour development.
4. The analysis of faeces, including the effect of diet on the contaminants, is discussed in relation to these methods.
SOME CHEMICAL CONSTITUENTS OF UTERINE WASHINGS: A METHOD OF ANALYSIS WITH RESULTS FROM VARIOUS SPECIES
Authors: HEAP R. B. 
Published: December 2008

SUMMARY
A technique is described for the recovery of uterine washings from four species, the rat, rabbit, sheep and cow. The washings were recovered from intact animals at oestrus and during the luteal phase of the reproductive cycle. The amounts of several chemical constituents were measured in the washings (sodium, potassium, chloride, phosphorus, iron, copper, aluminium, magnesium, calcium, cobalt, manganese, carbohydrate, lipid) and the nitrogen distribution was determined. The method, which involved flushing the uterine horn with an isotonic solution, was evaluated in terms of the recovery of a given volume of flushing solution, the effect of uterine ligation, post-mortem changes in the levels of chemical constituents in the uterine washings, and changes in the amounts of the different constituents in utero during the flushing procedure. There was a significant difference in the amount of several of the constituents in uterine washings recovered at two stages of the reproductive cycle. The values were greater at oestrus than at dioestrus in the rat (Na, K, Cl, N, carbohydrate), but greater in the luteal phase than at oestrus in the rabbit, sheep and, to some extent, in the cow (K, P, N, carbohydrate). The application of the method and the interpretation of the results are discussed.
THE INFLUENCE OF PROPYLTHIOURACIL AND THYROXINE ON SUPEROVULATION IN IMMATURE MICE
Authors: WILSON E. D. , CHAI C. K. 
Published: December 2008

SUMMARY
The influence of an altered thyroidal function on induced superovulation in B6AF1 mice has been investigated. The hypothyroid condition induced by feeding propylthiouracil (PTU) produced a significant increase in average numbers of ova from 20·3 to 28·7 (0·01 < P < 0·05). There was also an increase in ovarian weight from 42·7 to 86·5 mg./100 g. body weight (P < 0·001).
Six groups fed PTU were also injected with l-thyroxine daily for 6 days to produce hyperthyroidism. This resulted in a decrease in average numbers of ova from 28·7 to 17·0 (0·01 < P < 0·05). The level of thyroxine has a highly significant effect on ova count, but the data are not sufficiently precise to determine the form of the dose-response relation.
OBSERVATIONS ON CADMIUM DAMAGE AND REPAIR IN RAT TESTES AND THE EFFECTS ON THE PITUITARY GONADOTROPHS
Authors: ALLANSON M. , DEANESLY R. 
Published: December 2008

SUMMARY
Cadmium chloride, in a single subcutaneous injection, can destroy spermatogenic and interstitial cells in the rat testis (Pařízek, 1957) and produce changes in the pituitary. The interstitial tissue is restored by ingrowths from the tunica and full androgen secretion returns before there is any regeneration of germinal epithelium.
A cytological study has been made of the peripheral and central pituitary gonadotrophs; the latter revert almost to normal as the interstitial tissue regenerates, whereas the former retain characteristic castration features, unless there is also regeneration of the germinal epithelium. This seems to indicate that in the normal testis there is a hormone contribution from the seminiferous tubules as well as from the interstitial cells.
The long-term effects of cadmium on the testis depend on the dose. Early stages of tubule restoration have been studied, but after administration of 0·9 mg., actual proliferation of the germinal epithelium was rarely found—only in four out of twenty rats, 113 or 142 days after injection.
THE EFFECT OF NORETHYNODREL ON THE OVARIES AND PITUITARY GLAND OF ADULT FEMALE RATS
Authors: HOLMES R. L. , MANDL ANITA M. 
Published: December 2008

SUMMARY
Prolonged treatment with norethynodrel at a dose level sufficient to cause sterility did not consistently lead to blocking of ovulation. The ovaries of some of the animals were devoid of corpora lutea, while those of others contained variable numbers at different stages of development and regression. None of the treated animals, however, possessed as many corpora lutea as did their oil-injected controls.
The treatment also induced a variable degree of follicular inhibition. Typical and regular oestrous cycles were abolished.
The incidence of corpora lutea formed during the period of injection was slightly greater in animals housed with males than in those kept isolated. Although coitus was not followed by a period of pseudopregnancy, as judged by vaginal smears, most of the mated animals possessed corpora lutea resembling those of pseudopregnancy.
The pituitary gland of the norethynodrel-treated animals was heavier than that of their controls, due largely to an increase in the volume of tissue occupied by chromophobe cells. The proportion of basophil cells was lower, while that of eosinophil cells remained unchanged.
GLUCAGON-LIKE ACTIVITY EXTRACTABLE FROM THE GASTRO-INTESTINAL TRACT OF MAN AND OTHER ANIMALS
Authors: KENNY A. J. , SAY R. R. 
Published: December 2008

SUMMARY
Acid-ethanol extracts of different regions of the gut in man, dog, rabbit and pig were assayed for glucagon-like activity by the glycogenolytic response of liver slices.
Glucagon-like activity was present in the extracts of human stomach, including the pyloric region, and in the duodenum, jejunum and ileum. No activity was found in liver, spleen and blood. The stomach of the dog yielded higher activities than that of the human. Pig tissues contained little activity.
The properties of the active substance in the human gastro-intestinal tract were those of a peptide or protein in that it was non-diffusible during dialysis, precipitated by ammonium sulphate and destroyed by chymotrypsin. Glucagon behaves in a similar way in these respects.
THE FATTY ACIDS OF THE SERUM IN HYPOTHYROIDISM
Authors: LAWRIE T. D. V. , McALPINE S. G. , PIRRIE R. , RIFKIND B. M. , BLADES JEAN 
Published: December 2008

SUMMARY
The fatty acid patterns of the cholesterol ester, triglyceride and phospholipid fractions of serum from thirteen hypothyroid subjects have been determined using gas-liquid chromatography.
A comparison was made with the results of similar analyses performed on sixteen apparently normal subjects and on eighteen patients with ischaemic heart disease. A trend towards increasing saturation was found in each of the fractions from the hypothyroid subjects. This was most marked in the cholesterol esters.
The mechanism of the production of this trend is discussed and it is suggested that it is secondary to the hyperlipidaemia of hypothyroidism.
Attention is drawn to the implication of these findings in interpreting the reported changes in the fatty acid composition of the serum lipids in atherosclerosis.