bluuebunny/crossref_metadata_2025 huggingface dataset:
SPONTANEOUS HYPERADRENOCORTICISM IN THE DOG
Authors: RIJNBERK A. , der KINDEREN P. J. , THIJSSEN J. H. H.
Published: December 2008

Twenty-one dogs with spontaneous hyperadrenocorticism presented a clinical picture characterized by an insidious onset of abdominal enlargement, muscular weakness, obesity and alopecia. Slight diabetes mellitus was present in some. In the bitches usually there was absence of oestrus for a long time. In addition to polydipsia and polyphagia, features indicative of heat intolerance were observed frequently. The signs and symptoms found are compared to those of human Cushing's syndrome.

Determinations of the excretion of 17-hydroxycorticosteroids in 24-hr. urines were of great diagnostic significance. There was a considerable overlap of levels of plasma 11β-hydroxycorticosteroids in normal dogs and those with hyperadrenocorticism. Results of dexamethasone suppression tests are given.

In the sera of four exophthalmic animals and in one pituitary obtained by necropsy, elevated levels of exophthalmos-producing substance were found. Pathological findings have become available in a number of cases.

Preliminary results with hypophysectomy in four dogs are encouraging.
THE EFFECT OF FOLIC ACID ON SUPEROVULATION IN THE IMMATURE RAT
Authors: WILLMOTT MARY , BARTOSIK DELPHINE B. , ROMANOFF E. B.
Published: December 2008

The effects of the folic acid antagonist, 4-amino-N10-methylpteroylglutamic acid (methotrexate), and varying doses of folic acid were studied on superovulated immature rats. Methotrexate and folic acid were used alone and in combination with oestrone.

The parameters selected for study were organ weights and ovum counts. The administration of methotrexate (200 μg./rat), folic acid (400 μg.) or oestrone (500 μg.) partially inhibited ovulation. When given in combination with oestrone, both methotrexate and folic acid (50 μg.) reversed the fall in ovum counts produced by oestrone.

Because either a deficiency or an excess of folic acid partially inhibited ovulation, it is concluded that folic acid plays a significant role in induced ovulation in the immature rat. These effects are probably interrelated with the action of oestrogen.

In hypophysectomized immature rats, gonadotrophins increased ovarian and uterine weights when compared with those in untreated hypophysectomized animals, but the simultaneous administration of either methotrexate alone or combined with oestrone prevented these effects. Similar treatment of intact animals showed no differences in ovarian and uterine weights.
A TOPOGRAPHICAL STUDY OF AN HYPOTHALAMIC REGION WITH A 'THYROTROPHIC' ACTION
Authors: FLAMENT-DURAND J. , DESCLIN L.
Published: December 2008

In order to study the site of elaboration of the hypothalamic mediator which specifically influences the secretion of thyrotrophic hormone, pituitaries of 10-day-old donors were implanted into the hypothalamus of adult female rats. Some of the hosts were hypophysectomized, others were spayed 3 months before the administration of propylthiouracil (PTU) alone or in association with thyroxine. Thyroidectomy cells appeared in grafts placed in a zone which is distinct from the 'gonadotrophic' region we have previously described. The 'thyrotrophic' zone is more anterior and more dorsal and includes the suprachiasmatic region, the anterior hypothalamic region and the anterior part of the tuberal region. It extends dorsally including the paraventricular nuclei and a zone 1 mm. lateral of either side of these nuclei. The goitrogenic action of PTU occurs in hypophysectomized hosts even if the graft has no contact with the portal vessels. Simultaneous administration of thyroxine produces regression of the thyroid and of the thyroidectomy cells.
CHANGES IN THE VOLUME OF THE LOBES OF THE PITUITARY GLAND AND IN THE WEIGHT AND WATER CONTENT OF ORGANS OF RATS GIVEN HYPERTONIC SALINE
Authors: DUCHEN L. W.
Published: December 2008

The volume of the various lobes of the pituitary gland were measured in rats which were given 2% sodium chloride to drink instead of water. The volume of the posterior lobe was increased by 60% after 11 days on saline. The volume of the anterior lobe was slightly decreased but the volume of the pars intermedia was not changed. There was a marked loss of body weight in animals which were given saline and a marked reduction in the weight of the whole pituitary, liver and thyroid.
EFFECT OF CORTICOTROPHIN AND CORTICOSTEROIDS ON PLASMA INTERSTITIAL CELL-STIMULATING HORMONE AND URINARY STEROIDS IN THE BOAR
Authors: LIPTRAP R. M. , RAESIDE J. I.
Published: December 2008

Levels of interstitial cell-stimulating hormone (ICSH) activity in plasma estimated by the rat ovarian cholesterol depletion method and urinary gonadal steroid excretion were studied in boars under various experimental conditions. Injections of adrenocorticotrophic hormone (ACTH), hydrocortisone and prednisolone trimethylacetate were found to lower the level of plasma ICSH and urinary dehydroepiandrosterone (DHA) and oestrogens. This action of ACTH is thought to be mediated through the adrenal cortex since ACTH did not reduce urinary DHA or plasma ICSH activity in the adrenalectomized boar. Hydrocortisone reduced ICSH activity in the castrated boar. When hydrocortisone was administered at the same time as testicular steroidogenesis was stimulated by chorionic gonadotrophin in young hypophysectomized or intact boars, no pronounced influence was found on their elevated DHA excretion. It is concluded that in the boar some adrenal corticosteroids are capable of depressing plasma ICSH activity which results in reduced testicular steroidogenesis.
EFFECT OF STEROID HORMONES ON OESTROGEN-INDUCED UTERINE GLYCOGEN SYNTHESIS
Authors: CECIL HELENE C. , BITMAN J.
Published: December 2008

Uterine weight, water, glycogen and glucose responses were analysed for 96 hr. after a single dose or daily doses of oestradiol given to ovariectomized adult rats. Six hr. after a single dose of oestradiol the uterine glycogen concentration doubled, reached a maximum of 4 times the control value at 12 hr. and then declined during the 16–48 hr. period.

The ability of cortisol, deoxycorticosterone, progesterone, 17-ethyl-19-nortestosterone (Nilevar) or testosterone propionate to inhibit these responses was determined at 6 hr. (the initial period of maximum oestrogen action) and at 24 hr. (period of uterine glycogenolysis). A single injection of the antagonist given at the same time as oestrogen had no effect on the 6 hr. glycogen response. Pretreatment with cortisol, progesterone or testosterone propionate for 3 days caused a 30–50% inhibition of the oestrogen-induced increase. Multiple doses of testosterone propionate by itself were glycogenic. Single doses of the compounds appeared to be more effective at 24 hr. Multiple doses of cortisol, deoxycorticosterone, progesterone and testosterone propionate inhibited the 24 hr. glycogen response to oestradiol by 30–50%.
URINARY FREE CORTISOL MEASURED BY COMPETITIVE PROTEIN BINDING
Authors: BEARDWELL C. G. , BURKE C. W. , COPE C. L.
Published: December 2008

The technique of cortisol estimation by competitive protein binding analysis has been applied to the measurement of urinary free cortisol excretion. It has been found to be very sensitive and highly reproducible. There is good agreement with estimates of free cortisol excretion obtained by a chromatographic technique.

The mean normal excretion by a group of 24 convalescent patients without endocrine disease was 41·9 μg./24 hr. The range was 0 to 145·5 μg./24 hr. Eight obese patients showed values well within the normal range. The values found in eight cases of Cushing's syndrome ranged from 98·6 to 6100 μg./24 hr. There was very little overlap with the normal range.

Urinary free cortisol excretion was found to be a sensitive index of adrenal function during corticotrophin stimulation or dexamethasone suppression.
ATTEMPTED INDUCTION OF DECIDUOMATA IN MICE WITH MAST-CELL, CAPILLARY PERMEABILITY AND TISSUE INFLAMMATORY FACTORS
Authors: HUMPHREY K. W. , MARTIN L.
Published: December 2008

A variety of mast cell factors and other agents were injected into the uteri of pseudopregnant and progesterone-treated, ovariectomized mice. Oils, compound 48/80 (a histamine releaser) and one of three samples of bradykinin were the only stimuli that induced massive deciduomata in a high proportion of mice. The mast-cell factors, histamine, heparin and 5-hydroxytryptamine; carrageenin, several capillary permeability factors; oestradiol, polymyxin B, inflammatory extracts prepared from the subcutaneous tissue of mice, rats and rabbits, mouse uterine extracts, glass beads or electrical stimulation were of very low activity or were inactive. Air and dimethylsulphoxide induced large deciduomata in some mice. Intraperitoneal pyrathiazine was of low activity. Prior depletion of tissue histamine did not prevent the induction of deciduomata by local compound 48/80. It is concluded that the induction of deciduomata in mice is not dependent on histamine or other mast-cell factors or on capillary permeability or inflammatory factors.
A NEUROPHYSIN FROM COD (GADUS MORRHUA) PITUITARY GLANDS: ISOLATION AND PROPERTIES
Authors: PICKERING B. T.
Published: December 2008

A protein capable of binding neurohypophysial hormones has been isolated from cod pituitary glands using gel filtration and ion-exchange chromatography. The cod protein which was acidic and rich in cystine had an amino acid composition closely related to those of the mammalian neurophysins. It had a maximum binding capacity of 2·2 μmole/14mg. for oxytocin, 2·1 μmole/14 mg. for [8-arginine]-oxytocin and 1·1 μmole/14 mg. for [8-arginine]-vasopressin. Thus the cod protein had a greater capacity for the endogenous pressor-antidiuretic peptide than for the analogous mammalian hormone.
PROLACTIN ACTIVITY AND HUMAN GROWTH HORMONE IN PHARYNGEAL HYPOPHYSES FROM EMBALMED CADAVERS
Authors: McGRATH PHILOMENA
Published: December 2008

One hundred and forty-six human pharyngeal hypophyses from embalmed cadavers were fractionated in eight batches. A human prolactin-growth hormone extract was obtained from each batch. The prolactin activity of each extract was tested by the pigeon crop micromethod and the growth hormone content of the same extract was determined by radioimmunoassay. The results indicate that the human prolactin-growth hormone extract of pharyngeal hypophyses from embalmed cadavers retained prolactin activity and growth hormone to a significant degree despite adverse conditions post mortem. It is concluded that the human pharyngeal hypophysis is a tissue of functional significance. The apparent isolation of the pharyngeal hypophysis is of interest with regard to the role of the hypothalamus in the control of the sellar adenohypophysis. The functional significance of the pharyngeal hypophysis may be of importance in subjects for whom the total destruction of adenohypophysial tissue is considered to be of therapeutic value.
SECRETION OF C19-STEROIDS AND OESTROGENS IN THE POLYCYSTIC OVARY SYNDROME. OVARIAN STUDIES IN VIVO AND IN VITRO (INCLUDING STUDIES IN VITRO ON A COINCIDENTAL GRANULOSA CELL TUMOUR)
Authors: JEFFCOATE S. L. , BROOKS R. V. , LONDON D. R. , PRUNTY F. T. G. , RHODES P.
Published: December 2008

Ovarian metabolism of C19-steroids and oestrogens has been assessed at ovarian wedge resection in 22 patients with polycystic ovaries. There were marked variations between different patients.

High concentrations of androstenedione were found in ovarian vein plasma in some patients, and always after stimulation with human pituitary follicle-stimulating hormone (HP-FSH) in vivo. Its contribution to the daily production of testosterone has been considered. No measurable amounts of testosterone or dehydroepiandrosterone were found. Oestradiol concentration was sometimes normal or above.

Large amounts of androstenedione were generally isolated from cyst fluid. Occasionally testosterone was found and also epitestosterone after FSH. That concentrations of oestrogens in cyst fluid are low was confirmed, but sometimes higher levels were found after FSH.

Slices of ovarian tissue generally converted progesterone or pregnenolone to androstenedione in high yield but conversion to oestrogen appeared to be low. However, the difficulty of making quantitative comparisons by this method, in the absence of knowledge of the sizes of the pools of endogenous steroids in the tissue, has been recognized.

No evidence was found in any of the 18 cases examined for a lack of 3β-hydroxysteroid dehydrogenase.

In vitro synthesis of epitestosterone by both normal and polycystic ovaries has been observed.

A coincidental granulosa cell tumour in one patient synthesized testosterone in high yield.
METYRAPONE AND PYROGEN TESTS IN HYPERADRENOCORTICISM: EVALUATION OF BLOOD CORTICOTROPHIN LEVELS
Authors: LITTA-MODIGNANI R. , BADONI M.
Published: December 2008

Corticotrophin in blood was measured in four normal subjects and four patients suffering from Cushing's syndrome. The basal values of both groups were not statistically different. A standard Piromen test produced a statistically significant increase in normal patients; inconsistent results were obtained in hyperadrenocorticism. A metyrapone test showed significantly increased blood levels of ACTH in the normal subjects and a lower response in the patients with Cushing's syndrome. The Piromen test was also performed after 2 days of metyrapone administration (metyrapone-Piromen test). This test in normal patients induced an ACTH release that may be considered maximal (up to 17 m-u./100 ml.) presumably by relaxing the cortisol 'brake' on the hypothalamus; the response in the patients with hyperadrenocorticism was negative.
MONOAMINEOXIDASE INHIBITION AND INSULIN SENSITIVITY
Authors: ADNITT P. I.
Published: December 2008

Insulin sensitivity was increased in rats treated for 21 days with mebanazine, 10mg./kg., phenelzine, 30mg./kg., or tranylcypromine, 10 mg./kg. but not in rats treated with isonicotinic acid hydrazide, 10 mg./kg., for 21 days or in animals treated with a single injection of mebanazine, 10 mg./kg. Pargyline, 14 mg./kg., given for 21 days produced 83% inhibition of hepatic monoamineoxidase and had a hypoglycaemic action when compared with 0·15 mg. mebanazine/kg., a dose just less than that required to inhibit monoamineoxidase. Increased insulin sensitivity seemed to be related to chronic inhibition of monoamineoxidase rather than to administration of hydrazine derivatives.

There was a tendency to anorexia during the drug treatment, but rats treated with monoamineoxidase inhibitors gained less weight than pair-fed control animals. This could be due to the previously reported reduction in growth hormone activity during treatment with monoamineoxidase inhibitors; nevertheless, any explanation for the increase in insulin sensitivity should be based upon the monoamineoxidase-inhibiting action of these drugs.
PLASMA TESTOSTERONE IN WOMEN IN LATE PREGNANCY AND AFTER DELIVERY
Authors: DEMISCH K. , GRANT J. K. , BLACK W.
Published: December 2008

The concentration of testosterone was measured in the plasma of 16 healthy women in late pregnancy and in 14 of these after delivery. The mean testosterone concentration was found to be elevated in late pregnancy, although the range overlapped with the normal. There was a prompt return to normal concentrations after delivery. The significance of the results and of inactivation of testosterone by protein binding are discussed.
TISSUE AND SERUM CREATINE KINASE ACTIVITY IN HYPOTHYROID RATS
Authors: NUTTALL F. Q.
Published: December 2008

In rats made hypothyroid by thyroidectomy, serum creatine kinase (CK) activity appears to be unchanged or slightly reduced. This is in contrast to the increased values reported in myxoedematous man. Brain CK activity was unchanged and heart activity was only slightly reduced in these animals. Skeletal muscle CK activity, however, was more definitely reduced and the reduction was highly significant. The lower tissue enzyme activity in heart and skeletal muscle could be explained by a reduction in total protein concentration of the tissue extracts from the thyroidectomized animals, since the specific activity of the enzyme from these tissues was essentially unchanged as compared with controls.
COMPARATIVE EFFECTS OF THE OESTROGENS AND OTHER STEROID HORMONES ON SERUM LIPIDS AND PROTEINS IN XENOPUS LAEVIS DAUDIN
Authors: REDSHAW M. R. , FOLLETT B. K. , NICHOLLS T. J.
Published: December 2008

A comparison has been made between the effects of oestradiol-17β, oestrone, oestriol, progesterone, testosterone and cortisone on the plasma concentration of proteins and lipids in the South African clawed toad, Xenopus laevis Daudin. No major changes in the parameters studied were found with the non-oestrogenic steroids; only the three oestrogens induced the appearance in the plasma of a calcium-binding phospholipoprotein and esterified lipids associated with yolk formation. These results support the hypothesis that the oestrogens alone cause the vitellogenic response in oviparous vertebrates.

Dose—response curves for oestradiol-17β, oestrone and oestriol were established for the effects on plasma protein, calcium, protein-bound phosphorus, phospholipid, lipid and cholesterol. The curves obtained were log.-linear over the range of doses employed (oestradiol-17β, 1–50 μg./day; oestrone, 4–100 μg./day; oestriol, 20–500 μg./day) with the exception of the cholesterol response to oestradiol. The relative potencies of the three oestrogens were compared for each of the plasma components measured. Oestradiol-17β was the most potent, being 3·9 times more active than oestrone and 13·7 times more active than oestriol.
EVIDENCE FOR THYROCALCITONIN BINDING TO PROTEIN IN PLASMA
Authors: LEGGATE J. , CARE A. D. , FRAZER S. C.
Published: December 2008

A simple method is described for concentrating thyrocalcitonin from plasma by adsorption onto finely divided silica gel. An approximately 20-fold increase in biological activity with respect to protein content has been obtained with recoveries of added material of about 80%, allowing subsequent fractionation and bioassay of the fractions.

Porcine thyrocalcitonin was added to either porcine or human plasma to give concentrations within the range observed in porcine thyroid venous plasma. Concentration on silica gel followed by gel filtration on Sephadex G 50 resulted in separation of the biological activity into two fractions, one of which was associated with the plasma proteins. A similar result was obtained with porcine thyroid venous plasma containing endogenous thyrocalcitonin. Preparative ultracentrifugation of plasma rich in thyrocalcitonin also provided evidence suggestive of some protein binding of the hormone. It is concluded that thyrocalcitonin is carried in plasma partly free and partly bound to plasma protein.
THE RELEASE, CLEARANCE AND PLASMA PROTEIN BINDING OF OXYTOCIN IN THE ANAESTHETIZED RAT
Authors: FABIAN MIRIAM , FORSLING MARY L. , JONES J. J. , LEE J.
Published: December 2008

At 4°, the activity of exogenous 8-arginine vasopressin in rat plasma decreased to 50% in 2 days, whereas there was no loss of oxytocin under the same conditions after 3 days. At 37°, oxytocin was not inactivated in 9 hr., whereas 50% of 8-arginine vasopressin was lost in 2 hr.

Forty per cent of exogenous oxytocin in rat plasma was unable to pass through a cellophane (Visking 8/32 in.) membrane, when subjected to a pressure of 100 torr for 18 hr.

In rats under pentobarbitone anaesthesia, progressive haemorrhage of more than 2·0 ml./100 g. induced a secretion of both oxytocin and 8-arginine vasopressin, to produce maximum concentrations of 450 and 700 μ-u./ml., respectively, in the carotid plasma.

In the intact rat (weighing 200–250 g.) anaesthetized with pentobarbitone, 50% of oxytocin in the circulation disappeared within 2 min. after stopping an i.v. infusion of 250–6000 μ-u./100 g./min. The half-time was increased to 4 min. by sham operation, and to 6 or 7 min. by occluding either the renal, or the portal, coeliac and mesenteric vessels. In non-lactating animals, the half-time was 8 min. after clamping both the renal and splanchnic vessels, whereas it was 6 min. in the lactating rat, under the same conditions.

The apparent volume of distribution of oxytocin was 7·3 ml./100 g. in intact rats, and 10–13 ml./100 g. after operation.

The plasma clearance of oxytocin was unaltered in the sham-operated rat, but it decreased after the operative procedures.
LUTEINIZATION OF OVARIAN GRAFTS IN RATS RELATED TO TREATMENT WITH TESTOSTERONE IN THE NEONATAL PERIOD
Authors: LADOSKY W. , NORONHA J. G. L. , GAZIRI I. F.
Published: December 2008

Male Wistar rats were castrated on the day of birth and divided into two groups; the first was injected with 0·1 mg. testosterone propionate (TP), on the day of castration and the second with 0·5 mg. TP after day 10. When 45 days old, all were grafted with an ovary in the kidney. Animals in the first group showed ovaries with ripening follicles without corpora lutea; those in the second group had corpora lutea at different stages of maturation. Ovaries grafted into female rats spayed on the day of birth developed luteinization even when injected with 0·5 mg. TP after the 10th day of life, but not if the hormone was injected earlier.

Since the hypothalamus is sensitive to androgens only before the 10th day of life even in gonadectomized rats, it can be argued that the female pattern of gonadotrophin control does not correspond to the undifferentiated hypothalamus but depends on some active central mechanism. The period during which the hypothalamus is still sensitive to androgens would correspond to the undifferentiated equipotential stage.
THE CORPUS LUTEUM OF THE SHEEP: EFFECT OF THE CONCEPTUS ON LUTEAL FUNCTION AT SEVERAL STAGES DURING PREGNANCY
Authors: MOOR R. M. , ROWSON L. E. A. , HAY MARY F. , CALDWELL B. V.
Published: December 2008

The relationship between the conceptus and the corpus luteum during the first 90 days of pregnancy was determined in sheep which were made unilaterally pregnant by egg transfer 4 or 5 days after oestrus. Additional corpora lutea were established approximately 24 hr. after an injection of human chorionic gonadotrophin given on day 20, 30, 50 or 70, and 18–24 days later the sheep were killed.

When 17 unilaterally pregnant ewes, in which new corpora lutea had been induced on or before day 31, were killed, only the corpora lutea on the same side as the gravid horn were still functional; total regression of the corpora lutea had occurred in the ovary adjacent to the non-gravid horn. In 13 out of 14 sheep in which corpora lutea had been induced on day 51 or 71, the luteal tissue was still present in both ovaries at autopsy. Thus a local effect is exerted during the first one-third of pregnancy by conceptuses confined to one uterine horn, but this effect changes to a more general one about day 50.

In five sheep, embryos were allowed to develop in an intact uterus and under these conditions no unilateral effect could be demonstrated on corpora lutea induced on day 31.
NEUROHYPOPHYSIAL FUNCTION IN AMPHIBIA: HORMONE ACTIVITY IN THE PLASMA
Authors: BENTLEY P. J.
Published: December 2008

Blood plasma of dehydrated toads (Bufo marinus) and bullfrogs (Rana catesbeiana) increased water transfer (hydro-osmotic response) across the isolated toad urinary bladder. Sodium transport (in terms of the shortcircuit current) was also increased.

Immersion of Bufo marinus, Rana catesbeiana and Xenopus laevis (but not the neotenous newt Necturus maculosus) for 2 hr. in a 2% NaCl solution also increased the hydro-osmotic activity of plasma. Ether and haemorrhage also had this effect on plasma from Rana and Bufo.

Hydro-osmotic activity of plasma from dehydrated bullfrogs was destroyed by incubation with trypsin or tyrosinase, evidence which combined with the pharmacological effects of the plasma indicate that the hydroosmotic activity in the plasma is due to arginine vasotocin. The concentrations of this hormone were comparable with levels of antidiuretic activity observed in mammalian plasma.
STUDIES ON TISSUE CULTURE OF EQUINE OVARIAN CELL TYPES: STEROIDOGENESIS
Authors: CHANNING CORNELIA P. , GRIEVES SUSAN A.
Published: December 2008

Utilizing paper and gas—liquid chromatography, the pattern of steroid secretion by cultures of equine granulosa, thecal and stromal cells has been studied.

Granulosa cell cultures secreted primarily progesterone and 20α-hydroxypregn-4-en-3-one. A granulosa cell culture of 700,000 cells harvested from two large vascular follicles of a mare in oestrus secreted the following amounts of steroid from days 0 to 6 of culture: 561 μg. progesterone, 68 μg. 20α-hydroxypregn-4-en-3-one, 5·3 μg. 17-hydroxyprogesterone, 1 μg. androstenedione, 0·12 μg. dehydroepiandrosterone and 2·7 μg. oestradiol. Thecal tissue harvested from the same follicles secreted 29, 3·0, 1·8, 1·4, 1·1 and 0·99 μg., respectively, of the same steroids. All these steroids originated from endogenous precursors or from acetate or cholesterol in the tissue culture medium which contained 15% horse serum, 30% medium '199' and 55% Hanks's solution.

Cultures of granulosa cells harvested from two large vascular follicles of a mare in early oestrus secreted progesterone at a constant rate of 35 pg./cell/day between days 6 and 34 of culture, thus demonstrating that these cells do not dedifferentiate in culture. The secretion of 20α-hydroxypregn-4-en-3-one relative to progesterone increased from days 3 to 6 and remained constant from days 6 to 15.
A MODIFIED OVARIAN CHOLESTEROL DEPLETION ASSAY FOR LUTEINIZING HORMONE
Authors: ZARROW M. X. , CLARK J. H.
Published: December 2008

The ovarian cholesterol depletion assay for luteinizing hormone (LH) was investigated in the untreated immature rat. The prepubertal rat is a satisfactory animal to use in this assay because the diurnal rhythm in ovarian cholesterol is not present until puberty. A dose-response curve was obtained between 2·5 and 10·0 μ LH and the average lambda was 0·17. The assay was specific for LH; the presence of other pituitary hormones had no significant effect on the relative potency of NIH-LH preparations. The assay is probably not sensitive enough for untreated plasma but had excellent reproducibility and is easily performed.
UPTAKE OF [14C]5-HYDROXYTRYPTAMINE BY THE UTERUS OF RATS TREATED WITH OESTROGEN AND PROGESTERONE
Authors: KOREN E. , PFEIFER Y. , SULMAN F. G.
Published: December 2008

Radioactive [14C]5-hydroxytryptamine (5-HT, serotonin) creatinine sulphate was injected intrapleurally into female rats treated with oestrogen and/or progesterone which had received, immediately before the injection of 5-HT, homogenates of placenta, foetus, uterus or plasma, taken from pregnant rats on the 19th day of pregnancy. The placental homogenate produced a significant increase in 5-HT uptake by the myometrium, when the rats had been primed with moderate doses of oestrogen plus progesterone. Higher doses prevented the increased uptake, and oestrogen treatment alone did not induce 5-HT uptake. The highest level of 5-HT accumulation in the uterus was produced by placental extract after pretreatment with 0·5 mg. oestradiol plus 10 mg. progesterone/rat/day.

These results suggest that the placenta contains a 'trans-serotonin' system which is dependent on the oestrogen—progesterone balance and serves to accumulate 5-HT in the placenta and myometrium. Shifts of the hormonal balance may contribute to the release of 5-HT and thus promote uterine contractions at any stage of pregnancy.
THE RELATIVE POTENCIES OF OESTRIOL, OESTRADIOL AND OESTRONE ON THE UTERUS AND VAGINA OF THE MOUSE
Authors: MILLER B. G.
Published: December 2008

The effects of oestriol, oestradiol and oestrone on the uterus and vagina of the mouse have been investigated, by measuring changes in the incorporation of tritiated uridine into RNA, and in wet and dry organ weight. The time course of the uridine response to a single injection of oestriol differs markedly from that seen with single injections of oestradiol and oestrone. Oestriol has only a weak uterotrophic action in tests employing daily oestrogen injections, but when administered every 4 hr. in small doses it elicits as much growth in both organs as does oestradiol. The relative capacities of oestriol and oestradiol to sensitize the uterus to the induction of deciduomata by peanut oil are contrasted.
A SENSITIVE IN-VITRO METHOD FOR THE ASSAY OF CHOLECYSTOKININ
Authors: AMER M. S. , BECVAR W. E.
Published: December 2008

A sensitive assay method for cholecystokinin is described utilizing strips of rabbit gall bladder. The preparation is not responsive to secretin, histamine, or ammonium salts. The assay is more reproducible, sensitive and specific than other in-vitro methods.
THE SITES OF IODINE ACCUMULATION AND THE IODOAMINO ACIDS IN THE THYROID AND PLASMA OF PLAICE (PLEURONECTES PLATESSA L.)
Authors: OSBORN R. H. , SIMPSON T. H.
Published: December 2008

Whole body scanning and radioautography of plaice injected with 125I failed to show extra-pharyngeal sites of thyroid activity. The constituent iodoamino acids of thyroid tissue and of blood plasma have been identified by thin-layer chromatography of the parent compounds and of their derivatives, the preparation of which is described. Thyroid tissue has been found to contain 3,5,3′-tri-iodothyronine (T3), thyroxine (T4), 3-iodotyrosine (MIT) and 3,5-di-iodotyrosine (DIT). T3 and T4 were the only iodoamino acids detected in plasma.
GAS—LIQUID CHROMATOGRAPHY FOR ESTIMATION OF PERIPHERAL PLASMA PROGESTERONE IN DOMESTIC ANIMALS
Authors: STABENFELDT G. H. , EWING L. L. , PATTON J. P. , McDONALD L. E.
Published: December 2008

A method was adapted for the quantitative determination of progesterone obtained from the peripheral plasma of several domestic animals (cow, gilt and ewe). The technique utilized the detection of a chloroacetate derivative of 20β-hydroxypregn-4-en-3-one (enzymically converted from progesterone) by gas—liquid chromatography with electron capture detection. An improved extraction procedure is presented in which the plasma extract is saponified instead of the plasma; this was particularly effective for the removal of the yellow pigments normally found in large amounts in bovine plasma and allowed one-step isolation of progesterone by thin-layer chromatography. Progesterone levels in the peripheral plasma during the follicular phase of the oestrous cycle of the cow, gilt and ewe averaged 0·4 ng./ml., 0·5 ng./ml. and 0·2 ng./ml., respectively. Luteal phase levels of progesterone averaged 6·6 ng./ml., 27·1 ng./ml. and 2·1 ng./ml. in the cow, gilt and ewe, respectively. Progesterone increased during gestation in one cow from 4·7 (sixth month) to 6·1 ng./ml. plasma (eighth month). No evidence was obtained for a pre-ovulatory rise of progesterone in one cow during the 12 hr. immediately following oestrus.

It is suggested that corpus luteum function can be monitored in domestic animals during the oestrous cycle by the daily estimation of progesterone in the peripheral plasma.
THE EFFECT OF OESTRADIOL-17β ON ENZYMES CONCERNED WITH METABOLISM OF CARBOHYDRATE IN HUMAN ENDOMETRIUM IN VITRO
Authors: WILSON E. W.
Published: December 2008

Human endometrium in the regenerative phase was maintained for 5 hr. in vitro with oestradiol-17β alone or together with actinomycin D. Qualitative and quantitative histochemistry of the tissue showed that the activities of glucose-6-phosphate, 6-phosphogluconate, and lactate dehydrogenases were increased by oestradiol, and that actinomycin suppressed the hormonal effect. The activities of succinate and iso-citrate dehydrogenases were unaffected by oestradiol. An attempt is made to correlate the metabolic roles of the enzymes affected by oestradiol. The suppression, by actinomycin, of the oestradiol effect suggests that the increased enzyme activity is due to the formation of new enzyme protein.
STUDIES ON THE ENZYMIC FORMATION OF DI-IODOTYROSINE BY A MICROSOMAL PREPARATION OF GOAT SUBMAXILLARY GLAND
Authors: HATI RATHA N. , DATTA ASOKE G.
Published: December 2008

Subcellular fractions of goat submaxillary gland catalysed the iodination of monoiodotyrosine to form di-iodotyrosine; the microsomal fraction was found to have maximum activity. The enzyme needed copper or hydrogen peroxide for its activity. Thiourea and thiouracil inhibited the enzymic activity. Manganese and ferric ions inhibited the enzymic formation of di-iodotyrosine. The enzyme was solubilized by sodium desoxycholate treatment.
INDUCTION OF IMPLANTATION OF BLASTOCYSTS TRANSFERRED TO OVARIECTOMIZED MICE
Authors: HUMPHREY K. W.
Published: December 2008

Blastocysts transferred to progesterone-treated ovariectomized mice implanted only if oestradiol was given at or after transfer. A dose of 1·0 m.g. Provera/day maintained the implants to term. Omission of priming with oestradiol did not prevent implantation. Transfers performed on day 0, 1 or 2 of progesterone treatment were completely unsuccessful, while transfers on day 8 were less effective than those performed on day 3 or 4. Administration of oestradiol 24 or 48 hr. beforehand did not prevent the induction of implantation by a second dose of oestradiol, and did not render the uterus 'refractory'. Treatment with 8 ng. oestradiol on days 1 to 5 or day 4 or 5 induced implantation of blastocysts transferred on day 4.

It is concluded that oestrogen is not released as a surge before implantation, but is released continuously after ovulation.
SEX DIFFERENCE IN THE RELEASE OF LUTEINIZING HORMONE EVOKED BY PROGESTERONE
Authors: TALEISNIK S. , CALIGARIS L. , ASTRADA J. J.
Published: December 2008

Long-term gonadectomized female and male rats showed increased plasma luteinizing hormone (LH) activity (as measured by the ovarian ascorbic acid depletion method). A single injection of 20 μg. oestradiol benzoate or 2·5 mg. testosterone propionate after 3 days reduced the raised values significantly. Progesterone injected into gonadectomized rats primed with gonadal steroids exerts a positive feed-back action on the release of LH. In ovariectomized rats the injection of progesterone 3 days after a single injection of oestradiol or testosterone induced, a few hours later, a significant increase in plasma LH. In contrast, castrated male rats responded to progesterone with an increase in plasma LH only when they had been primed 3 days before with testosterone. This difference was not eliminated by gonadectomy on the first day of life. Androgen-sterilized ovariectomized rats failed to show an increase in plasma LH after progesterone when primed with testosterone but did so after priming with oestradiol. In male rats treated with testosterone in the early neonatal period, the normal LH release induced by progesterone in testosterone-primed animals was abolished. It is concluded that separate female and male patterns of LH release evoked by progesterone exist in the rat, and the difference between them is not determined by a postnatal differentiation in the neural mechanism which controls the secretion of LH.
THE BINDING OF [1,2-3H]TESTOSTERONE WITHIN NUCLEI OF THE RAT PROSTATE
Authors: MAINWARING W. I. P.
Published: December 2008

The specificity of the binding of [1,2-3H]testosterone to nuclei of various rat tissues in vivo has been studied. A significant amount of radioactivity was retained in the nuclei of androgen-dependent tissues only, particularly the ventral prostate gland. The bound radioactivity was only partially recovered as [1,2-3H]testosterone; the remainder was identified as [3H]5α-dihydrotestosterone. Efforts were made to characterize the binding component, or 'receptor', in prostatic nuclei. On digestion of nuclei labelled in vivo with [1,2-3H]testosterone, with enzymes of narrow substrate specificity, only trypsin released tritium, suggesting that the receptor is a protein. On the basis of subfractionation studies of labelled nuclei, the receptor is an acidic protein. The androgen—receptor complex could be effectively extracted from the prostatic nuclei in 1 m-NaCl and from the results of fractionations on a calibrated agarose column, the complex has a molecular weight 100,000–120,000. The specificity of the binding of steroids to such 1 m-NaCl extracts in vitro was investigated by the equilibrium dialysis procedure. Under these conditions, the specificity of the binding of [1,2-3H]testosterone demonstrated in vivo could not be simulated. The receptor is probably part of the chromatin complex but its precise intranuclear localization cannot be determined by biochemical procedures alone.
FOLLICLE-STIMULATING HORMONE CONTENT OF THE PITUITARY GLAND BEFORE IMPLANTATION IN THE MOUSE AND RAT
Authors: BINDON B. M.
Published: December 2008

The method of Lamond & Bindon (1966) was used to measure follicle-stimulating hormone (FSH) in the pituitary glands of mice and rats killed at different times on each of days 1–6 of pregnancy. The sensitivity of the method allowed detection of FSH fluctuations not previously described in these species.

A significant fall in pituitary FSH occurred in both species on day 3, although it was earlier in the mouse than in the rat. This transient decline in FSH activity, interpreted as a release of the hormone, was followed in both species by a gradual increase on days 4 and 5. Ovarian weight, measured only in the mouse, increased significantly late on day 3 and is believed to reflect changes in pituitary FSH.

The results indicate that implantation in the mouse and rat is initiated by altered activity of the pituitary gland during the first 3 days of pregnancy. It appears that this pituitary mechanism differs from that responsible for the events of the oestrous cycle.
CHANGES IN SIALIC ACID IN THE TESTIS AND EPIDIDYMIS OF THE RAT DURING THE ONSET OF PUBERTY
Authors: RAJALAKSHMI M. , PRASAD M. R. N.
Published: December 2008

The content and concentration of sialic acid in the testis, caput epididy-midis, cauda epididymidis and ductus deferens show changes during the transition from the prepuberal to the puberal (mature) state in the rat. The peak of sialic acid is attained in the caput epididymidis and cauda epididy-midis and ductus deferens between days 40 and 45 prior to the entry of sperms into these regions. Following the entry of sperms there is a sharp decline in sialic acid till day 60 in the caput epididymidis and ductus deferens while in the cauda epididymidis the decline in sialic acid is only transient between days 45 and 50 and is followed by sharp increase at day 60. Efferent duct ligation caused a marked decrease in content of sialic acid in the caput epididymidis only. The significance of these changes is discussed in relation to the maturation of spermatozoa.
POSSIBLE INTERACTION OF LUTEINIZING HORMONE-RELEASING FACTOR WITH OTHER HYPOTHALAMIC RELEASING FACTORS AT THE LEVEL OF THE ADENOHYPOPHYSIS
Authors: CRIGHTON D. B. , SCHNEIDER H. P. G. , McCANN S. M.
Published: December 2008

Anterior pituitary halves from adult male rats were incubated in vitro for 6 hr. in tissue culture Medium 199. Luteinizing hormone (LH) released from these glands under the influence of purified preparations of growth hormone-releasing factor (GH-RF), growth hormone-inhibiting factor (GH-IF), corticotrophin-releasing factor (C-RF) and follicle-stimulating hormone-releasing factor (FSH-RF) was determined by the ovarian ascorbic acid depletion (OAAD) assay. The effects of these factors, both alone and together with purified luteinizing hormone-releasing factor (LH-RF), were examined and compared with the response to purified LH-RF alone. While LH-RF consistently produced significant increases in LH release, none of the other factors did so, although FSH-RF showed some indication of LH-releasing activity, probably due to incomplete separation from LH-RF on the Sephadex gel filtration column used for purification. The LH released in response to LH-RF was not affected by the presence of any of the other factors. An apparent slight augmenting effect of FSH-RF could be accounted for by its contamination with LH-RF. The results are discussed in relation to the physiological mechanisms concerned in modifying LH release from the adenohypophysis.
IODINATION OF SERUM PROTEINS IN VIVO: RELATIONSHIP TO IRRADIATION AND HYPERTROPHY OF THE THYROID
Authors: TRIANTAPHYLLIDIS E. , THOMPSON B. D. , BARNABY C. F. , JASANI B.
Published: December 2008

High levels of labelled serum protein were found in rats with hypertrophied and colloid-depleted thyroids, but only after high thyroid irradiating doses of 131I. Low levels were found in rats with normal thyroids after low or high thyroid irradiating-doses of radioactive iodine. The levels in rats with hypertrophied thyroids after low thyroid-irradiating doses of 125I did not differ greatly from those in rats with normal thyroids. The mechanism of serum protein labelling is discussed and it is suggested that similar conditions may be important for the production of high levels of labelled serum protein in patients treated with radioactive iodine for functioning thyroid carcinoma.
THE METABOLISM OF [4-14C]CHOLESTEROL IN THE PRE-VIABLE HUMAN FOETUS
Authors: COUTTS J. R. T. , MACNAUGHTON M. C.
Published: December 2008

After perfusion of pre-viable human foetuses with [4-14C]cholesterol for up to 2 hr., radioactivity was widely distributed in the foetal tissues. Most of the radioactivity was recovered as unchanged cholesterol but traces of pregnenolone and 17α-hydroxypregnenolone were isolated from the liver and adrenals. No steroid conjugates were isolated although small amounts of cholesterol sulphate may have been formed and solvolysed during extraction. Judging from these results the human foetus at mid-term is unlikely to be able to synthesize progesterone from cholesterol and is dependent on a placental supply of progesterone.
OESTRIOL IN AMNIOTIC FLUID: A GAS CHROMATOGRAPHIC METHOD
Authors: BIGGS J. S. , KLOPPER A. , WILSON G. R.
Published: December 2008

A method is described for estimating oestriol in amniotic fluid. The main steps of the method are acid hydrolysis, chemical purification and methylation, chromatography on alumina columns, acetylation and estimation by gas chromatography. A radioactive internal standard is employed to correct for losses during assay. Data on the reliability of the method are given.
THE FATE OF FREE AND CONJUGATED OESTROGENS INJECTED INTO THE GRAAFIAN FOLLICLE OF EQUINES
Authors: GIORGI ELEONORA P. , ADDIS M. , COLOMBO G.
Published: December 2008

[4-14C]Oestradiol-17β, [4-14C]oestrone, Na[6,7-3H]oestradiol-17β-glucuronide and Na[6,7-3H]oestrone sulphate were injected into a Graafian follicle of two mares and a donkey after cannulation of the ovarian vein. Radioactivity was measured in follicular fluid and ovarian venous blood at different intervals after injection and in tissue and interstitial fluid at the end of the operation. Both free and conjugated oestrogens were retained to a great extent in the follicle, in the presence of constant production of endogenous oestrogens. Only a small portion of the oestrogen released from the follicle passed directly into the ovarian venous blood; a larger portion entered the effluent blood indirectly, through interstitial fluid and tissue. The conjugates, particularly the glucuronide, seemed to be excluded from the cells and accumulated in the interstitial fluid.

The role of binding of oestrogens to fluid proteins in the retention of oestrogen in follicular fluid is discussed.
THE FUNCTIONAL CAPACITY OF OVARIAN TISSUE TRANSPLANTED TO THE SPLEEN OR KIDNEY IN THE FERRET
Authors: DONOVAN B. T.
Published: December 2008

Ovarian tissue was autografted to the spleen or kidney of spayed anoestrous or oestrous ferrets to see whether inactivation of ovarian hormones occurred in the liver and to examine the feedback action of gonadal hormones on gonadotrophin secretion. Although the grafts survived in both sites as did homografts made in anoestrous females, the secretion of gonadal hormones was sufficient to cause oestrus only in a minority of animals and there was little difference in the function of grafts made to the spleen or kidney. Vulval swelling and uterine growth were caused by pellets of oestradiol inserted into the spleen so that it appears that this steroid can pass through the liver without loss of oestrogenic activity. It is concluded that little inactivation of gonadal steroids by the liver of the ferret takes place.
AN ASCENDING PATHWAY FOR RELEASE OF PROLACTIN IN THE BRAIN OF THE RABBIT
Authors: TINDAL J. S. , KNAGGS G. S.
Published: December 2008

Rabbits in pentobarbitone anaesthesia were implanted bilaterally with a pair of monopolar electrodes in the brainstem. Approximately 10 days after the operation, pseudopregnancy was induced by i.v. injection of human chorionic gonadotrophin, and 1 week later the rabbits received electrical stimulation with square-wave pulses through the implanted electrodes for two periods of 30 min. daily for 11 days. At autopsy on the following day the mammary glands were inspected for occurrence of lactogenesis and sites of electrode tips in the brain were determined histologically. Lactogenesis, indicating release of prolactin, occurred when electrical stimulation had been applied to sites in the lateral mesencephalic tegmentum and further forward in a region medio-ventral to the medial geniculate body. Passing rostrally, the pathway moved medially and then forwards in association with the extreme rostral central grey matter, and was traced as far forward as the posterior hypothalamus where sites were found close to, but not involving, the mammillo-thalamic tracts.

When compared with our previous studies on the afferent path of the milk-ejection reflex in this species, the ascending path for release of both oxytocin and prolactin appears to be the same in the mesencephalon. However, whereas the ascending path for oxytocin release bifurcates on each side into dorsal and ventral paths which reunite in the posterior hypothalamus, that for prolactin release appears to follow only the dorsal path, since stimulation of the subthalamus, through which the ventral path passes, was ineffective. It is proposed that the pathway traced in the present study represents the mesencephalic and posterior diencephalic route by which impulses initiated by the suckling stimulus attain the hypothalamus to evoke release of prolactin from the adenohypophysis.
STUDIES ON THE PRESSOR SUBSTANCES OF THE CAUDAL NEUROSECRETORY SYSTEM OF TELEOST FISH: BIOASSAY AND FRACTIONATION
Authors: CHAN D. K. O. , JONES I. CHESTER , PONNIAH S.
Published: December 2008

A method for the bioassay of the pressor substances in extracts of the urophyses of the teleost fish, Mugil auratus and Anguilla anguilla, is described. Ultracentrifugation, chromatography on Sephadex gel and treatment with trypsin and papain showed that the pressor principles are polypeptides. One fraction was protein-bound while two other fractions seem to be small molecules. Treatment with thioglycollate showed that disulphide bonds do not form an integral part of the active molecule.

The possible function of these principles in the control of the caudal circulation is discussed.
THE INFLUENCE OF THE PINEAL GLAND ON NITROGEN METABOLISM
Authors: MILCU IOANA , NANU-IONESCU LYDIA , MARCEAN RODICA , IONESCU VIOLETA
Published: December 2008

The influence of the pineal gland on protein metabolism was investigated by using a test previously devised for studying the anabolic action of growth hormone. This test consists in measuring the accumulation of urea in blood after the intravenous administration of an amino acid mixture to nephrectomized rats injected with the test substance. Like growth hormone, pineal extract significantly reduced the quantity of urea formed, suggesting an anabolic action. In contrast, in pinealectomized animals, the quantity of urea formed significantly increased when compared with controls.