bluuebunny/crossref_metadata_2025 huggingface dataset:
HORMONAL MODULATION OF HYPOTHALAMIC UNIT ACTIVITY AND EEG RESPONSE TO VAGINAL STIMULATION IN THE DEERMOUSE
Authors: ZOLOVICK A. J. , ELEFTHERIOU B. E.
Published: December 2008

The EEG after-reaction to vaginal stimulation occurred during oestrus and was inhibited during dioestrus or abolished by pregnancy or ovariectomy. Hypothalami of oestrous animals were more responsive to vaginal stimulation than the hypothalami of dioestrous or pregnant animals. The increase in the number of responsive neurones in oestrous animals was attributed to an increase in the number of neurones that exhibited a delayed decline in their discharge rate in response to vaginal probing. These neurones were located along the midline in the anterior and basal hypothalamus. Administration of oestrogen to ovariectomized animals was moderately successful in reinstating the delayed inhibitory response of the hypothalamic neurones to vaginal stimulation while the EEG response was almost completely restored. The importance of this hypothalamic activity is discussed in relation to the luteinizing hormone short loop feedback mechanism and the EEG after-reaction.
EFFECT OF REDUCED FOOD INTAKE ON THYROID CELL HEIGHT AND GOITROGENIC RESPONSE IN RATS
Authors: DONIACH I. , SWETTENHAM K. V.
Published: December 2008

Adult rats in groups of ten were maintained variously on full, half and quarter food intake. Some were given plain drinking water ad libitum, others were given a goitrogenic challenge of 0·1% aminotriazole (ATA) in the drinking water. Food and fluid consumption were measured daily. The animals were killed after 3 weeks for measurement of thyroid and body weight. The thyroids were histologically examined and epithelial cell height was measured. Another series of rats on normal food intake were given ATA solutions of various concentrations to drink and the efficacy of the concentrations to depress a 16 h thyroid uptake of 131I was measured.

The results showed a reduction in average thyroid cell height parallel to the degree of starvation in the non-ATA treated groups and a reduction in goitrogenic response to equivalent challenge with ATA of about 15% in the half-fed animals and 20–25% in the quarter-fed animals. It is suggested that, in adapting to caloric restriction, higher centres depress the thyrotrophic hormone releasing factor response of the hypothalamus to a fall in circulatory thyroid hormone concentration. The degree of reduction in goitrogenic response might be regarded as a quantitative index of this depression.
GENETIC VARIATION IN ADRENAL WEIGHT IN YOUNG ADULT MICE
Authors: BADR F. M. , SPICKETT S. G.
Published: December 2008

Adrenal weight and body weight were measured for 100 mice of each sex of the strains: A/Cam, CBA/FaCam and SF/Cam. This was also done for reciprocal F1 hybrids between A and CBA, for reciprocal backcrosses, and for F2 hybrids. Using regression analysis, adrenal weights were corrected for differences in body weights. Sexes and strains were found to be significantly different with respect to both absolute and corrected adrenal weight. The males of the F1 cross between the A and CBA strains showed partial dominance of the A genotype. Reciprocal F1 females were found to differ significantly. This may be explained in terms of parent-genotype: offspring-genotype interactions.

The variances of the heterogeneous stocks: F2, backcross of F1 to A and backcross of F1 to CBA, were found to be significantly higher than those of the homogeneous stocks: A, CBA and F1's. This indicated that at least some of the variation in relative adrenal weight between the strains was genetically determined. The frequency distributions of the ratio of adrenal weight to body weight in F2 and reciprocal backcrosses conformed to the classical pattern of a metrical character.
ACTIONS OF MAMMALIAN, AVIAN AND PISCINE GONADOTROPHINS IN THE LIZARD
Authors: LICHT P. , HARTREE ANNE STOCKELL
Published: December 2008

The gonadotrophic activities of crude glycoprotein fractions from pituitaries of man, sheep, chicken and carp and of partially purified follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the three tetrapod species were examined in both sexes of the lizard Anolis carolinensis. The piscine material did not show activity in the lizard but all mammalian and avian preparations promoted spermatogenesis, ovarian growth, ovulation and steroidogenesis. FSH preparations were far more potent than LH, in fact the actions of the LH preparations may have been due largely to FSH contamination. These findings are consistent with earlier conclusions that FSH alone may be able to stimulate all types of gonadal activity in lizards, except that high doses of FSH block ovulation. Comparisons of the relative potencies of the avian and mammalian preparations provide evidence for the zoological specificity of vertebrate gonadotrophins. In general, the relative potency of chicken gonadotrophins in lizards was greater than that estimated from standard rodent bioassays: i.e. the lizard is relatively more sensitive to chicken gonadotrophin than the rodent.
FUNCTIONAL ZONATION OF ADRENOCORTICAL TISSUE IN THE BRUSH POSSUM (TRICHOSURUS VULPECULA)
Authors: VINSON G. P. , PHILLIPSt J. G. , JONES I. CHESTER , TSANG W. N.
Published: December 2008

The relationship of structure and function in the adrenal gland of the possum Trichosurus vulpecula, has been studied using in-vitro incubation techniques. It was shown that both 17α-hydroxycorticosteroids and 17-deoxycorticosteroids were produced from radioactive pregnenolone and progesterone, and that these transformations occurred both in the definitive cortex as well as in a special zone of hypertrophied tissue found only in the adult female.

In support of earlier findings, it was also shown that the adrenal cortex of the possum has a remarkable capacity to produce C19 steroids (including androstenedione and testosterone) from the radioactive precursors. While most of the transformations occurred with equal efficiency in both types of tissue, the reduction of androstenedione to testosterone seemed to take place more readily in the special hypertrophied zone of the adult female.

In studies in vivo, it was found that levels of testosterone in the peripheral blood of the adult female possum were extremely high compared with man. Variations in testosterone levels were not apparently correlated with the stage of the oestrous cycle.

The possible pathways by which the adrenal products are synthesized, and their physiological implications are discussed.
URINARY EXCRETION OF FREE CATECHOLAMINES IN GRAVES' DISEASE
Authors: BAYLISS R. I. S. , EDWARDS O. M.
Published: December 2008

As judged by the urinary excretion of free noradrenaline and adrenaline, the secretion of catecholamines is not increased in patients with Graves' disease. Catecholamine excretion was not reduced by treatment with propranolol or carbimazole singly or in combination. The possible mechanism in hyperthyroidism responsible for the apparent increase in sympathetic nervous activity and the mitigation of these features by propranolol is discussed.
EFFECT OF OESTRADIOL ON CELL PROLIFERATION AND HISTOLOGICAL CHANGES IN THE UTERUS AND VAGINA OF MICE
Authors: GALAND P. , LEROY F. , CHRÉTIEN J.
Published: December 2008

The duration of the phase of DNA synthesis (S-phase) and turnover times were measured by autoradiography in the vaginal and endo-uterine epithelium of spayed mice at different times after a single oestradiol injection. With three doses of oestradiol (0·3, 1·2 and 10·0 μg), changes of turnover time followed similar patterns in uterine epithelium, but maximal activation and subsequent levelling off of proliferation rates were reached sooner with higher doses. In the vagina, no significant dose-dependence was apparent with the same doses of oestradiol; maximal activation of cell proliferation was observed in every case 12 h after hormone injection.

Transient shortening of S-phase was observed in both tissues under oestrogen stimulation. The morphological changes in uterine epithelium appeared to be independent of mitotic stimulation. For vaginal epithelium, the results may be interpreted to indicate that oestrogen-induced keratinization starts by a differentiating action on pre-existing G1 cells.
THE 'EARLY ANDROGEN SYNDROME' IN THE GUINEA-PIG
Authors: BROWN-GRANT K. , SHERWOOD M. R.
Published: December 2008

When testosterone propionate was administered to pregnant guinea-pigs over a short period (days 33–37) of gestation a high proportion of the female offspring exhibited a characteristic syndrome. The time of the first vaginal opening was delayed and its duration reduced. Subsequent periods of opening were fairly regular in occurrence but were shorter in duration than in normal animals; the 'cycle' length was usually slightly longer. Continuous vaginal opening was not observed but during the periods of opening, vaginal smears containing many cornified cells and no leucocytes were obtained. During the periods of vaginal opening no lordosis response to manual stimulation could be elicited nor did the animals mate when run with males. The increase in body weight was normal up to about 150 days of age and slightly, but not significantly, less than that of controls between 150 and 200 days of postnatal life. As adults some masculinization of the external genitalia was observed. At autopsy the weights of the uteri, ovaries, adrenal and anterior pituitary glands were much greater than those of control animals at any stage of the cycle. Histological examination showed that the ovaries contained many antral follicles but no luteal tissue. Enlargement of the glands and metaplastic changes in the epithelium were observed in the uteri. The pituitaries showed an excess of cells containing large, densely packed eosinophilic granules.

This early androgen syndrome is compared with that produced by hypothalamic lesions in the guinea-pig and with the changes produced in other species by the administration of androgenic steroids during prenatal or early postnatal life.
THE EFFECT OF SURGICAL ISOLATION OF THE HYPOTHALAMUS ON REPRODUCTIVE FUNCTION IN THE FEMALE RAT
Authors: BUTLER JEAN E. M. , DONOVAN B. T.
Published: December 2008

Surgical isolation of the hypothalamus from the rest of the brain was used in a study of the hypothalamic control of gonadotrophin secretion. Rats with hypothalamic islands of differing sizes and animals in which the hypothalamus was partially deafferentated were prepared. Oestrous cycles were followed by taking daily vaginal smears and the reproductive state assessed from histological examination of the genital tract collected at autopsy 28 days postoperatively. In rats with 'large' and 'long' hypothalamic islands persistent vaginal oestrus ensued and the ovaries were follicular. Rats in which smaller islands disconnected the suprachiasmatic nuclei from the median eminence displayed persistent vaginal dioestrus and the ovaries contained corpora lutea. Rats with frontal cuts placed anterior to the suprachiasmatic nuclei behaved similarly to rats with 'large' and 'long' islands in developing persistent vaginal oestrus, but when the anterior connexions to the hypothalamus were severed caudal to the suprachiasmatic nuclei the animals had oestrous cycles which were sometimes interrupted by periods of dioestrus of pseudopregnancy length. Posterior and transverse cuts in the hypothalamus did not alter the oestrous cycle although there was some indication that luteal function was favoured.
THE SECRETION OF IMMUNO-REACTIVE LUTEINIZING HORMONE AND FOLLICLE-STIMULATING HORMONE BY THE HUMAN FOETAL PITUITARY IN ORGAN CULTURE
Authors: GROOM G. V. , GROOM M. A. , COOKE I. D. , BOYNS A. R.
Published: December 2008

Foetal human pituitaries of 8–18 weeks gestational age were maintained in tissue culture for up to 6 days. No morphological change was observed in the tissue during this period. Radioactive glucosamine was continuously incorporated into medium protein and the levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH) and growth hormone in the medium increased with the duration of the culture. Theophylline stimulated the release of both LH and FSH consistently over the 6 days, and the total amount of each hormone released over this period was significantly greater than that in unstimulated control cultures. Cyclic adenosine 3′,5′-monophosphate stimulated FSH release to some extent but had no significant effect on LH release.
DIFFERENTIAL STIMULATION BY PARATHYROID HORMONE OF BONE AND KIDNEY RIBONUCLEIC ACID SYNTHESIS
Authors: STEINBERG J. , NICHOLS G.
Published: December 2008

The effects of parathyroid extract (PTE) on the synthesis in vivo of free nucleotide and RNA were compared in rat metaphysial bone and kidney. The incorporation of 32P into chromatographically pure acid-soluble 5′-AMP and purified bulk RNA was examined at various times after PTE administration. Pulse-labelled RNA was further characterized by sedimentation in sucrose density gradients and by ribomononucleotide analysis.

In both organs the labelling of 5′-AMP and its turnover were accelerated after administration of the hormone. The pool size of free AMP of kidney was approximately 3 times that of bone; neither was affected by PTE. The specific activity of pulse-labelled kidney AMP was always greater, and hormonal stimulation of its labelling was more rapid than in bone.

Despite more extensive precursor labelling, the stimulation of renal RNA synthesis was negligible, and was delayed for several hours, the overall hormonal effect being inseparable from its effect on phosphate entry into the nucleotide precursor pool.

In bone, the hormonal stimulation of RNA labelling was immediate, and continued to increase at a linear rate for up to 12 h. Initially, stimulation of RNA polymerization accounted for the total hormonal effect, while after 4 h an increasing proportion of the total increase in RNA labelling was attributable to enhanced precursor labelling.

Newly synthesized bone RNA differed qualitatively from kidney RNA in its sedimentation properties and composition. Although the labelling of all RNA species and RNA-nucleotides in bone was stimulated by PTE, there was a proportionately greater effect on the labelling of ribosomal RNA, and an apparent shift towards GMP-rich molecules, neither change being manifest in kidney.

It is concluded that while bone and kidney share certain mechanisms, they show changes in RNA biosynthesis in response to parathyroid hormone which are both quantitatively and qualitatively different and which are in accord with the RNA requirements for the respective physiological response of each.
THE METABOLISM OF TESTOSTERONE BY SKIN IN NORMAL SUBJECTS AND IN TESTICULAR FEMINIZATION
Authors: JENKINS J. S. , ASH S.
Published: December 2008

The metabolism in vitro of testosterone by normal human skin has been studied and the results have been compared with those obtained in two cases of testicular feminization. The predominant metabolite was 5α-dihydrotestosterone followed by androstenedione, androsterone, and 5α-androstanedione.

Suprapubic skin from patients with testicular feminization metabolized testosterone in a completely normal manner. There was no evidence to support the view that a failure to produce an essential metabolite of testosterone is responsible for the condition of testicular feminization.
THE ANDROGENIC RESPONSE OF THE GENITAL ACCESSORY ORGANS OF THYROXINE-TREATED AND CASTRATED RATS EXPOSED TO COLD
Authors: DAS R. P. , PERRAULT M. J.
Published: December 2008

The role of the thyroid in cold-induced atrophy of the genital accessory organs and the protection by treatment with testosterone against such atrophy have been evaluated in intact and castrated male rats.

Treatment with thyroxine or exposure to cold reduced the weight and some of the activities of the genital accessory organs in intact but not in castrated rats.

Testosterone propionate implants not only protected these organs from the cold-induced atrophy but also stimulated them beyond the level of intact controls kept at room temperature.

The weight and some functions of the genital accessory organs of testosterone-treated castrated rats were decreased after cold exposure. These changes were more pronounced when thyroxine was administered simultaneously.

The results suggest that the cold-induced atrophy of the accessory organs is due to the release of excess thyroid hormone and that implants of testosterone propionate can prevent this atrophy.
THE MAINTENANCE OF PREGNANCY DURING THE PRE-IMPLANTATION PERIOD IN MICE TREATED WITH PHENELZINE DERIVATIVES
Authors: ROBSON J. M. , SULLIVAN F. M. , WILSON CATHERINE
Published: December 2008

A number of derivatives of the mono-amine oxidase inhibitor (MAOI) compound, phenelzine, have been shown to have an anti-fertility effect, when administered both before and after implantation in mice. The action of the compounds in the pre-implantation period (days 1–6) is reversed by progesterone and by prolactin; both have to be given with 0·05 μg oestradiol/mouse during days 4 and 5 to induce implantation. When the oestrogen treatment is omitted implantation is delayed by 2–3 days. This seems to be due to a transient antagonism of the action of luteinizing hormone (LH), which is necessary for the secretion of oestrogen which in turn is necessary for implantation. In addition, the MAOI compounds appear to inhibit the release of pituitary hormones necessary for the maintenance of pregnancy. In the pre-implantation period the important pregnancy-maintaining hormone seems to be prolactin, and after implantation LH seems to become the main luteotrophin.
INCREASED SEBUM SECRETION IN ADULT FEMALE RATS AFTER NEONATAL TREATMENT WITH TESTOSTERONE PROPIONATE
Authors: THODY A. J. , SHUSTER S.
Published: December 2008

Testosterone propionate (TP) was administered to female rats at 3 and 6 days of age. When adult the sebum secretion rate of these rats was significantly increased, although the response to TP was normal.

Neonatal androgen treatment had no effect on the preputial gland weight of adult female rats. On the other hand ovarian weight was reduced.

After ovariectomy of normal adult rats there was an increase in sebum secretion to a level comparable to that found in adult rats given TP as neonates. By contrast there was no change in sebum secretion after ovariectomy of adult rats given TP as neonates and the rate of sebum secretion in these rats was comparable to that in ovariectomized normal adults.

It is suggested that after neonatal androgen treatment the normal inhibition of the sebaceous glands by the ovaries was abolished and consequently the rate of secretion was increased. Thus the endocrine state in early life may have a lasting effect on sebaceous gland activity in the adult.
INHIBITION OF COMPENSATORY OVARIAN HYPERTROPHY IN MICE BY MELATONIN, 5-HYDROXYTRYPTAMINE AND PINEAL POWDER
Authors: VAUGHAN MARY K. , BENSON B. , NORRIS J. T. , VAUGHAN G. M.
Published: December 2008

Single injections of melatonin, 5-hydroxytryptamine or pineal powder on the day of operation significantly blocked compensatory ovarian hypertrophy in unilaterally ovariectomized mice in a dose-related fashion. Inhibition of compensatory ovarian hypertrophy by melatonin was most effective when the compound was given on the day of dioestrus and least effective on the day of pro-oestrus. These results support the conclusion that the pineal gland elaborates one or more substances which have an antigonadotrophic action in the female rodent.
A METHOD FOR DETERMINING THE DISTRIBUTION AND SOURCE OF PROTEIN IN PREOVULATORY RAT OVARIES
Authors: LIPNER H. , SMITH M. SUSAN
Published: December 2008

The distribution and source of protein in the fluid compartments of tissues may be determined by the use of [14C]sucrose to determine the volume of the fluid compartments and 125I-labelled serum albumin ([125I]SA) to determine the distribution volume of the labelled protein. The amount of tissue protein in the ovary, the amount of protein derived from plasma, the rate of plasma protein influx into the ovary and the amount of newly synthesized protein were calculated.

Immature female rats were treated with pregnant mare serum gonadotrophin (PMS)when 24 days old and were given human chorionic gonadotrophin (HCG) 42 h later. The rats were given [14C]sucrose or [125I]SA and measurements were made. Ovaries and blood were collected 0, 3, 5, 8 and 10 h after HCG administration. At all intervals the dry weight represented 14% and water 86% of the weight of the ovary. The extracellular space increased until 8 h and then both it and the intracellular space increased. At 0 h plasma protein accounted for 17% of the total proteins. At 10 h the ovarian weight had increased by 50% to 100% of the value at 0 h and the total protein by 45% of the value at 0 h with plasma protein accounting for 27% of the total proteins, and newly synthesized protein for 16%. The increase in plasma protein was linear and accumulated at the rate of 15%/h. By this method no entrance of plasma protein into the intracellular space could be demonstrated. Newly synthesized protein appeared only after 5 h and probably represents the growth of a new crop of follicles.
THE ROLE OF PROGESTERONE IN REGULATING THE PERIOD OF SEXUAL RECEPTIVITY IN THE FEMALE HAMSTER
Authors: CIACCIO L. A. , LISK R. D.
Published: December 2008

Spayed female hamsters were given a 150 μg pellet of oestradiol s.c. (day 0). After s.c. placement of a 200 μg pellet of progesterone 7 days later, all animals displayed oestrous behaviour. Treatment with 200 μg progesterone suspended in propylene glycol or sesame oil, on days 4, 5 or 6 also induced an immediate period of heat but subsequent placement of a 200 μg pellet of progesterone on day 7 did not always result in oestrous behaviour. The animals did not show the lordosis response after placement of the progesterone pellet on day 7 when 200 μg progesterone in sesame oil had been given on either day 5 or 6. In contrast, when propylene glycol was employed as the vehicle, only injection on day 6 blocked oestrous behaviour on day 7.

When the same amount of progesterone in propylene glycol was administered on day 5, as injections of 50 μg each over 12 h or more, progesterone in propylene glycol was more effective in blocking oestrous behaviour on day 7. The injection on day 5 of 100 μg progesterone in propylene glycol as four injections of 25 μg over 12 h did not block oestrous behaviour on day 7. The injection of 50 μg progesterone in propylene glycol on four successive nights induced a period of sexual receptivity after each injection. These observations indicate that the duration of the insensitive condition, developing as a result of a period of progesterone-facilitated heat, is a function of the amount of hormone causing the initial receptive period, as well as the duration of progesterone stimulation.
CONGENITAL ADRENAL HYPERPLASIA AND OTHER CONDITIONS ASSOCIATED WITH A RAISED URINARY STEROID 11-OXYGENATION INDEX
Authors: CLAYTON BARBARA E. , EDWARDS R. W. H. , MAKIN H. L. J.
Published: December 2008

Raised values of the 11-oxygenation index (11-OI) were found in 164 children, although it was only possible to record 97 fully. Seventy-four were fully diagnosed as having congenital adrenal hyperplasia (CAH) and among the others five had high 11-OI values which fell to normal by the 8th day of life and two gave high values due to methodological interference by 1-oxygenated steroids. Severe diarrhoea was associated with a raised 11-OI in ten boys and this presented difficulty in diagnosis; CAH was considered a possible diagnosis by the referring physician but was finally excluded.

Impaired adrenocortical function probably accounted for the raised 11-OI observed in six children who were never considered to have CAH. They had a variety of conditions including congenital heart disease.

Normal 11-OI values were found in six patients with adrenocortical tumours. Prednisone and prednisolone administration interfered with the determination.
THE PRODUCTION OF HORMONAL STEROIDS BY OVARIAN TISSUES OF THE CHINCHILLA (CHINCHILLA LANIGER)
Authors: TAM W. H.
Published: December 2008

The corpora lutea of pregnancy (primary CL), corpora lutea atretica (accessory CL), and the residual tissue (consisting of interstitial cells and a few follicles) were dissected from pregnant chinchilla ovaries, and incubated separately using [7α-3H]pregnenolone as substrate. Tritiated progesterone, 20α-hydroxypregn-4-en-3-one, androstenedione, testosterone and oestradiol-17β were identified as products. [7α-3H]Progesterone was the major hormone synthesized (yield 36–85%) by the three types of ovarian tissues, but the two types of luteal tissue were more efficient in the production of this compound. Androstenedione and oestradiol-17β were also synthesized by all the tissues incubated. The large amount of androstenedione produced suggested that it was the immediate oestrogen precursor. However, the occurrence of traces of 17α-hydroxyprogesterone and dehydroepiandrosterone made it impossible to conclude whether the 4- or 5-unsaturated pathway was preferred for the synthesis of oestrogens.

Endogenous progesterone, 20α- and 20β-hydroxypregn-4-en-3-one, and oestradiol-17β concentrations in the plasma were also determined using gas—liquid chromatography. The major hormone was again progesterone. Since abortion occurred after ovariectomy, these hormones must have been of ovarian origin.

The findings suggest that the accessory corpora lutea supplemented the primary corpora lutea in the production of hormones for the maintenance of gestation.
HORMONAL REGULATION OF RNA AND PROTEIN SYNTHESIS IN THE MOUSE MAMMARY GLAND BEFORE AND DURING LACTATION
Authors: BANERJEE M. R. , ROGERS FERNE M. , BANERJEE D. N.
Published: December 2008

As measured by [3H]uridine incorporation in vivo, the low rate of RNA synthesis in the mammary gland of virgin C3H and BALB/c mice increased sixfold in the mammary tissue of 15-day pregnant mice. In the 5-day lactating gland, RNA synthesis was ten times higher than that in virgin mammary tissue. On the 10th day of lactation this increased RNA synthetic activity in the mammary gland was considerably reduced but was still twice that of the mammary tissue of virgin mice. Twenty-four hours after adrenalectomy, RNA synthesis in lactating glands was reduced by over 80%, whereas in the mammary gland before lactation, it was reduced by 20–30% only. A single i.p. injection of 250 μg of cortisol led to a threefold increase of RNA synthesis within 1 to 2 h in lactating glands of adrenalectomized mice; this was followed by a decline. Incorporation of [3H]leucine into trichloroacetic acid-insoluble material from lactating mammary tissue was used as a measure of'total protein' synthesis, and [3H]leucine radioactivity determined in Ca2+−rennin precipitate of 105000 g supernatant of lactating mammary tissue homogenate was used as a measure of casein synthesis. Adrenalectomy caused a 50% reduction of 'total protein' synthesis, whereas synthesis of 'casein-like' phosphoprotein virtually stopped after the operation. The injection of cortisol into adrenalectomized mice induced a selective increase of [3H]leucine incorporation into the casein of lactating glands. The results indicate that RNA synthesis in the mammary tissue is more dependent on adrenal hormones during the functional than the structural state of differentiation. The hormonal regulation of RNA synthesis and its role in milk protein synthesis in the mammary gland in vivo is discussed.
THE EFFECTS OF CORTICOTROPHIN, GLUCOSE AND POTASSIUM CHLORIDE ON SECRETION BY THE NASAL SALT GLAND OF THE DUCK, ANAS PLATYRHYNCHOS
Authors: PEAKER M. , PEAKER STEPHANIE J. , PHILLIPS J. G. , WRIGHT A.
Published: December 2008

Ducks given corticotrophin (ACTH) i.m. for 5 days secreted significantly more nasal fluid in response to an i.v. injection of 0·5 m-NaCl. However, blood glucose and plasma potassium concentrations also increased in the birds given ACTH and when these changes in blood composition were produced by injecting glucose or KC1, an effect similar to that of ACTH was obtained, suggesting that glucocorticoids influence the salt gland indirectly rather than, or as well as, directly. The concentrations of Na+ and K+ in the nasal fluid were decreased by ACTH, an effect not mimicked by glucose or KC1, and this might suggest some direct influence on water movements in the salt gland. ACTH increased nasal secretion in response to a minimal stimulatory salt load approximately 15 min after i.v. injection and this increase coincided with a marked rise in blood glucose concentration.
INHIBITION OF LIPOLYSIS AND POTENTIATION OF THE HYPOGLYCAEMIC EFFECT OF INSULIN BY NON-HYPOGLYCAEMIC INSULIN DERIVATIVES
Authors: DILMAN V. M. , VASIL'EVA I. A.
Published: December 2008

Treatment of insulin with iodine or formaldehyde eliminates its hypoglycaemic effect but does not affect the antilipolytic properties of insulin. Pharmacological doses of iodinated insulin injected into rabbits inhibit the lipolysis caused by human growth hormone, corticotrophin, lipotrophin or fasting.

Iodinated or formaldehyde-treated insulin was found to increase the hypoglycaemic effect of exogenous native insulin. This action may be accounted for by the antilipolytic activity of these insulin derivatives. Iodinated insulin could also be shown to decrease the glycaemia after a glucose load.

The significance of increased lipolysis in the pathogenesis of a large group of pathological conditions caused by increased resistance of the hypothalamus to homeostatic inhibition is discussed.
STEROIDS OF A CHONDROSTEAN: CORTICOSTEROIDS AND TESTOSTERONE IN THE PLASMA OF THE AMERICAN ATLANTIC STURGEON, ACIPENSER OXYRHYNCHUS MITCHILL
Authors: SANGALANG G. B. , WEISBART M. , IDLER D. R.
Published: December 2008

Double isotope derivative assays were used to determine the presence or absence of testosterone, cortisol, cortisone, corticosterone, 11-deoxycortisol and 11-deoxycorticosterone in plasma samples from two (one sexually immature and one sexually mature) male American Atlantic sturgeon, Acipenser oxyrhynchus Mitchill. Submicrogram levels of testosterone were detected in the dichloromethane-extractable ('free' steroid) fractions of the plasma samples from both the immature and the mature fish; the level was much higher in the plasma of the mature fish. Very low levels of 'free' cortisol, cortisone and corticosterone were also detected in the plasma of the immature fish. The presence of 11-deoxycorticosterone and 11-deoxycortisol could not be firmly established in any of the samples. Preliminary analysis for conjugated testosterone in the plasma of the immature fish failed to show any detectable enzyme-released testosterone.
INDUCTION OF TARGET ORGAN INSENSITIVITY TO TESTOSTERONE IN THE MALE GUINEA-PIG WITH CYPROTERONE
Authors: GOLDFOOT D. A. , RESKO J. A. , GOY R. W.
Published: December 2008

Male guinea-pigs born to females injected with cyproterone acetate (CA) from day 28 to 58 of gestation developed non-tubular hypospadiac penes and stunted seminal vesicles and prostate glands. When adult animals were stimulated with exogenous or endogenous androgens, secretory failure and only minimal growth was observed in the accessory organs. The concentrations of endogenous testosterone in systemic plasma from intact CA males were not different from those in control males, but the uptake and distribution of [1,2-3H]testosterone in castrated CA males did not conform to control values. Deficiences in mounting, intromission and ejaculatory patterns were observed in CA males compared with controls. Lordosis, the primary behavioural response used as a criterion of 'feminization', was never observed in CA males even when large concentrations of oestrogens were administered. The results suggest that target organ insensitivity to testosterone in adulthood can be the result of deficient androgenic stimulation during embryological differentiation.
THE EFFECTS OF PORCINE CALCITONIN ON RENAL FUNCTION IN THE RABBIT
Authors: SALAKO L.A. , SMITH A. J. , SMITH R. N.
Published: December 2008

Extracts of porcine thyroid containing calcitonin produced increases in urinary flow and urinary electrolyte content when infused or injected into anaesthetized rabbits. This response occurred more rapidly after intraaortic than after intravenous injection and was accompanied by an increase in glomerular filtration rate (inulin clearance) and renal plasma flow (paraaminohippuric acid clearance).

Preparations of calcitonin failed to affect the short-circuit current in isolated frog skin.

Although an effect of calcitonin on renal tubular transport mechanisms cannot be excluded it seems likely that one mechanism responsible for the diuretic effect of this compound in the rabbit is an increase in renal blood flow.
RELATIONSHIP OF MITOSIS TO ALVEOLAR DEVELOPMENT IN THE RAT MAMMARY GLAND
Authors: DILLEY W. G.
Published: December 2008

After 3 and 5 days of culture of whole rat mammary glands in the presence of insulin, or insulin plus prolactin, or insulin plus prolactin plus aldosterone, or insulin plus prolactin plus oestradiol plus progesterone, there was good correlation between the levels of alveolar development and the [3H]thymidine labelling indices. Blockage of mitosis in explants developing in medium containing insulin plus prolactin also blocked alveolar development. Alveolar development is therefore proportional to and dependent on mitotic activity in the proper hormonal environment.
BLASTOCYSTS IN THE MOUSE UTERUS: THE EFFECT OF OVARIECTOMY, PROGESTERONE AND OESTROGEN
Authors: McLAREN ANNE
Published: December 2008

The effects of ovariectomy at different stages of early pregnancy, and the response to various amounts of exogenous progesterone and oestrogen, were studied in Q-strain mice. When the ovaries were removed on the third day of pregnancy, unimplanted blastocysts were retained in the uterus and no lysis of the zona pellucida occurred; removal on the following morning permitted lysis of the zona pellucida but again no implantation; by the afternoon the ovaries were no longer required for the initiation of implantation, but in the absence of progesterone no sites were maintained. A single dose of oestrogen eliminated all unimplanted blastocysts from the uteri of ovariectomized mice. Daily treatment with a low dose of progesterone after ovariectomy on the third day altered the appearance of the uterus but did not permit implantation unless oestrogen was also given. Under all the above conditions, some reduction in the number of embryos occurred. The maximum number of implantation sites in ovariectomized mice was achieved by daily injection of a high dose of progesterone, with no added oestrogen. An intermediate level of progesterone induced abortive implantation in mice ovariectomized on the third day, and abnormal development of implantation sites after ovariectomy on the fourth day. When the start of progesterone injections was postponed, either after ovariectomy or during lactational delay, it proved more difficult to induce implantation with the progesterone preparation alone, in the absence of added oestrogen.
THYROXINE BINDING TO ANTITHYROID ANTIBODIES: EFFECTS OF ALTERED METABOLIC STATUS
Authors: POGORILER G. , van MAANEN J. H. , SELLERS E. A.
Published: December 2008

Thyroxine-binding antithyroid antibodies produced by hetero- or isoimmunization were examined in animals in different metabolic conditions. Guinea-pigs and rats were treated with thyroxine (T4) or methimazole or kept at 4 °C. During treatment they were immunized with heterologous or isologous thyroid extracts. Control animals were given liver extracts or saline. Rabbits were hetero- or iso-immunized but otherwise were untreated.

All thyroid-immunized animals had a significantly higher level of tracer thyroxine binding in the globulin fraction of serum than had controls, regardless of metabolic status. Only thyroid hetero-immunized animals showed anti-thyroid antibodies as measured by routine immunological tests.

In serum from animals with high levels of T4, less tracer was bound in the globulin fraction. This change did not represent a decrease in the amounts of T4 bound by the antibodies, but rather a redistribution of the hormone in the serum proteins.

Methimazole decreased not only the specific thyroxine binding by the antithyroid antibodies but also the non-specific binding in the globulin fraction of control serum. Adaptation to cold apparently did not affect the thyroxine binding to the antibodies.
SIMULTANEOUS COMPARATIVE STUDIES OF THYROXINE AND TRI-IODOTHYRONINE DISTRIBUTION AND DISPOSAL RATES
Authors: McCONNON J. , ROW V. V. , VOLPÉ R.
Published: December 2008

Determinations of the total serum tri-iodothyronine (T3) and total serum thyroxine (T4) were performed in healthy persons, and in patients with various thyroid diseases. In addition, tracer doses of 131I-labelled T3 and 125I-labelled T4 were given intravenously, and the disappearance rates of each hormone were plotted graphically. From this single injection slope-intercept technique, the volumes of distribution, half-times, fractional rates of disappearance, and hormonal production rates were calculated by standard techniques. In normal persons, the average T3 production was 44·75 μg daily, and that for T4 97·30 μg/day. In most hyperthyroid patients, the production of both hormones was increased in equal proportions to the normal group. In four patients with 'T3-thyrotoxicosis', the total serum T4 and T4 production rates were within normal limits, and only T3 production was increased. In patients with primary hypothyroidism, the production of both hormones was reduced: however, T4 production was more markedly reduced than T3 production. Two patients with Hashimoto's disease who were clinically euthyroid showed low T4 production rates, but T3 production was almost within normal limits. These findings suggest that in primary thyroid deficiency there appears to be a sequential failure of T4 production and then of T3 production, before hypothyroidism develops clinically. This may be due to increased endogenous thyrotrophin, and perhaps a low intrathyroidal iodine content. In contrast, patients with secondary hypothyroidism due to hypopituitarism had much higher ratios of T4:T3 production rates than patients with primary hypothyroidism.
EFFECTS OF THE INTERRUPTION OF AMYGDALOID AND HIPPOCAMPAL AFFERENTS TO THE MEDIAL HYPOTHALAMUS ON GONADOTROPHIN RELEASE
Authors: VELASCO M. E. , TALEISNIK S.
Published: December 2008

The effects of interruption of amygdaloid and hippocampal afferents to the hypothalamus on ovulation and on the release of luteinizing hormone (LH) were studied in rats. Animals acutely deprived on the morning of pro-oestrus of amygdaloid influences either by transection of the stria terminalis (ST) or lesions of the amygdala, failed to show the expected ovulation. Control lesions had no effect. In contrast, rats with long-term transection of either the ST, the cortico-hypothalamic tract (CHT), or both, had regular oestrus cycles and ovulated normally. Studies of ovulation which was induced after the administration of ovarian steroids revealed a differential response to oestrogen and progesterone. In animals with long-term transection of the ST the ovulatory response to oestrogen was similar to that induced in non-lesioned rats but fewer ovulations were induced by progesterone administration. The decreased ovulatory response after progesterone treatment was attributed to activation of inhibitory influences originating in the hippocampus, since administration of picrotoxin or section of the fornix re-established a normal response. Long-term interruption of the limbic efferents did not alter the increased levels of plasma LH found after ovariectomy. However, the release of LH induced by progesterone in ovariectomized rats primed with gonadal steroids was decreased after transection of the ST and increased after interruption of the CHT. These results are consistent with the concept that the amygdala and the hippocampus exert a modulating influence on gonadotrophin release; the influence of the amygdala being facilitatory and that of the hippocampus inhibitory.
ADENYL CYCLASE AND PHOSPHODIESTERASE ACTIVITY IN THE ISOLATED ISLETS OF LANGERHANS OF OBESE MICE AND THEIR LEAN LITTER MATES: THE EFFECT OF GLUCOSE, ADRENALINE AND DRUGS ON ADENYL CYCLASE ACTIVITY
Authors: ATKINS T. , MATTY A. J.
Published: December 2008

Radiometric estimations of adenyl cyclase and cyclic AMP (cAMP) phosphodiesterase showed significantly higher enzyme activities in the islet tissue of obese-hyperglycaemic mice than in that of their normal litter mates, but the ratios of the two enzymes in both types of islets were found to be the same, i.e. 1:1.

Adenyl cyclase and phosphodiesterase activity increased linearly with incubation time and protein concentration. Sodium fluoride (10 mmol/1) increased cyclase activity in the islets of obese mice by 33·4%; theophylline (10 mmol/1) in the presence of cAMP (1 mmol/1) reduced phosphodiesterase activity by almost 100%.

Glucose (2 g/1) reduced, while adrenaline (10−5 mol/1) increased cyclase activity in islets from both normal and obese animals. An evaluation of the effects of α- and β-adrenergic receptor stimulating and blocking agents on islets of both normal and obese mice showed the stimulation of adenyl cyclase to be a β-adrenergic receptor function and the inhibition an α-adrenergic receptor function. The possible role of the adenyl cyclase system in diabetes mellitus and insulin secretion is discussed.
ULTRASTRUCTURAL CHANGES ACCOMPANYING INVOLUTION OF THE MAMMARY GLAND IN THE ALBINO RAT
Authors: RICHARDS R. C. , BENSON G. K.
Published: December 2008

Adult female rats undergoing their first lactation were experimentally weaned by removing their pups on day 4 of lactation. The initial phase of mammary gland involution began with the removal of protein granules from the milk by digestion in large stasis vacuoles in the alveolar epithelial cells. Later stages involved a progressive necrosis of the epithelial cells by auto-phagocytosis. Removal of fat droplets and cellular debris occurred at this time and was accomplished by macrophage-like cells. Finally, epithelial cells were detached from the basement membrane and were found, in varying stages of degeneration, lying free in the lumina of the alveoli.
HUMAN PROLACTIN. EVIDENCE OBTAINED BY THE BIOASSAY OF HUMAN PLASMA
Authors: FORSYTH ISABEL A. , MYRES RITA P.
Published: December 2008

Single plasma samples from 27 control subjects and from 18 women in early lactation have been assayed for lactogenic activity using a semi-quantitative rabbit mammary gland organ culture method. Tests with a variety of anterior pituitary, posterior pituitary, placental and steroid hormones have shown the method to be specific for prolactin and for prolactin-like hormones such as human growth hormone (HGH) and human chorionic somatomammotrophin (HCS). Twelve of the 18 samples from women in early lactation gave positive lactogenic responses, while only one of the control samples did so. Plasma HGH levels were measured by radioimmunoassay. The levels of HGH in the medium, resulting from addition of plasma, were in all cases below the limits of sensitivity of the assay. The conclusion that human prolactin immunologically distinct from HGH is being measured is supported by the failure of antiserum to HGH to affect the in-vitro lactogenic response to plasma. Assay of fractions prepared from plasma by gel filtration suggests a molecular weight of approximately 20000 for the lactogenically active material.
PREPARATION AND PROPERTIES OF SUBUNITS OF HUMAN LUTEINIZING HORMONE
Authors: HARTREE ANNE STOCKELL , THOMAS MARJORIE , BRAIKEVITCH MARY , BELL E. T. , CHRISTIE D. W. , SPAULL G. V. , TAYLOR ROSEMARY , PIERCE J. G.
Published: December 2008

Separation of the subunits of human pituitary luteinizing hormone (LH) has been accomplished by dissociation of the hormone with 8 m-urea followed by chromatography on CM-cellulose at pH 5·0 or by counter-current distribution. Each procedure resulted in isolation of one subunit, the other subunit being contaminated with reassociated LH. The isolated subunits (α and β) are each of low biological activity, but when recombined in a 1:1 ratio at pH 7, reassociation occurs with restoration of full activity. The amino acid compositions of the two subunits are significantly different from each other, but the composition of the α subunit is very similar to published data on the corresponding subunit of human chorionic gonadotrophin (HCG) and human thyroid-stimulating hormone. Significant differences were observed when comparing the compositions of the β subunits of the hormones. By immunoradiometric assay using antibodies to HCG, the α subunit was as active as native LH on a weight basis, but the β subunit was significantly lower in immunological activity.
EFFECTS OF ADRENALECTOMY ON DAILY RHYTHMS IN OXYGEN CONSUMPTION OF TISSUES IN THE GROWING RAT
Authors: GOULDING J. , BELLAMY D.
Published: December 2008

Daily rhythms in oxygen consumption were demonstrated in liver and skeletal muscle of male rats. Rhythms were observed only in skeletal muscle of females and in some cases there appeared to be a sex difference in the overall level of respiration. Respiration rhythms were not found in cardiac muscle of either sex. The effect of adrenalectomy upon the rhythms was examined. This indicated that the adrenal does not determine the phasing of the rhythms but does control the basal level of tissue oxygen uptake.
EFFECT OF PROLACTIN ON NUCLEIC ACID METABOLISM DURING LACTOGENESIS IN THE RABBIT
Authors: SIMPSON A. A. , SCHMIDT G. H.
Published: December 2008

Lactogenesis was initiated by intraductal injection of prolactin into individual lobes of rabbit mammary glands previously developed by injections of oestrogen and progesterone. Nucleic acid metabolism was assessed at various times after prolactin treatment. A systemic pulse of [3H]thymidine or [3H]uridine was used to determine the specific effects of prolactin treatment on RNA and DNA synthesis and metabolism.

Prolactin increased the rate of RNA synthesis. It is suggested that prolactin enhanced both the rate of RNA movement from the nucleus, and its rate of metabolism in the cytoplasm. The greatest increase in the rate of synthesis occurred in non-ribosomal RNA. Subsequent to its effect on RNA, prolactin enhanced DNA synthesis. Total RNA per cell increased as indicated by an increased RNA:DNA ratio. These changes are considered to be specifically due to the local action of prolactin.
5-NUCLEOTIDASE, ACID PHOSPHATASE AND PHOSPHORYLASE DURING NORMAL, DELAYED AND INDUCED IMPLANTATION OF BLASTOCYSTS IN MICE: A HISTOCHEMICAL STUDY
Authors: HALL KATHLEEN
Published: December 2008

The distribution of histochemically demonstrable 5′-nucleotidase activity in the uterus of mice around the time of nidation, is compared with those of specific and non-specific acid phosphatases, alkaline phosphatase, phosphorylase, and with deposition of glycogen. The sequences of changes in distribution were similar during normal (first pregnancy) or delayed (by lactation) implantation, or when implantation was induced in lactating mice by administration of hormones.

5′-Nucleotidase activity was located at the free border of the luminal epithelium and at surfaces of stromal cells and muscle fibres up to the time of implantation, and in non-decidualized areas after implantation, but disappeared from differentiated decidual cells. The disappearance of 5′-nucleotidase activity from decidual cells occurred at the time when their mitotic activity was waning and when alkaline phosphatase activity had appeared at their surfaces, and lagged slightly behind both glycogen deposition and increased phosphorylase activity in these cells. There was parallel distribution of phosphorylase activity and glycogen distribution within decidua.

At the time of implantation, a reaction appeared in stromal cells in the immediate vicinity of the blastocyst after incubation with either adenosine-5′-monophosphate or glycerophosphate at acid pH, and it spread in area during the next 24 h. It was believed to indicate activity of a non-specific acid hydrolase, possibly lysosomal.

In all uteri examined, epithelial cells of glands showed specific acid phosphatase, but no 5′-nucleotidase activity.