bluuebunny/crossref_metadata_2025_split huggingface dataset:
THYROXINE BINDING TO ANTITHYROID ANTIBODIES: EFFECTS OF ALTERED METABOLIC STATUS
Authors: POGORILER G. , van MAANEN J. H. , SELLERS E. A. 
Published: December 2008

SUMMARY
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

SUMMARY
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

SUMMARY
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

SUMMARY
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

SUMMARY
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

SUMMARY
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

SUMMARY
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

SUMMARY
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

SUMMARY
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

SUMMARY
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.
CONCENTRATIONS OF OESTROGEN AND PROGESTERONE IN THE PLASMA OF NON-PREGNANT, PREGNANT AND LACTATING GUINEA-PIGS
Authors: CHALLIS J. R. G. , HEAP R. B. , ILLINGWORTH DOREEN V. 
Published: December 2008

SUMMARY
A competitive protein-binding assay of progesterone and a radioimmunoassay of total unconjugated oestrogens were evaluated and employed in the measurement of these steroids in the plasma of guinea-pigs at different times during the reproductive cycle. Production rates (PR) were calculated from the product of the endogenous steroid concentration and its metabolic clearance rate. During the oestrous cycle, plasma progesterone levels rose from undetectable levels at the time of ovulation to 2·8 ± 0·33 (s.e.m.) ng/ml 5 days later; PR was 0·26 mg/day. During pregnancy, plasma progesterone concentrations in post-partum mated guinea-pigs rose from 15 ng/ml at day 15 post coitum (p.c.) (PR, 0·65 mg/day) to a peak value of 329 ± 14 ng/ml by days 30 to 45. The concentration fell 51–55 days p.c. (160 ± 14·7 ng/ml), but rose before parturition to 258 ± 22 ng/ml. After day 20 p.c., PR was 1·24 ± 0·3 mg/day. After parturition, plasma progesterone levels fell rapidly and during lactation were about 10 ng/ml (PR, 0·4 mg/day).
Total unconjugated oestrogens in arterial plasma were not detected in early pregnancy, but rose from values of 12·8 ± 1·9 pg/ml (days 31–35) to 31·0 ± 5·2 pg/ml (days 56–60). There was a slight fall before, and a rapid one after parturition. The ratio of progesterone to oestrogen in plasma fell during pregnancy and reached its lowest values between days 55 and 60.
ESTIMATION OF URINARY GONADOTROPHINS BY BIOASSAY AND RADIOIMMUNOASSAY
Authors: BUTT W. R. , LYNCH S. S. 
Published: December 2008

SUMMARY
The results of the application of a solid-phase radioimmunoassay for follicle-stimulating hormone (FSH) to 376 24-h urine specimens assayed routinely by the ovarian augmentation method for FSH, and 663 24-h urine specimens assayed routinely by the uterine weight method for total gonadotrophins, are presented. The correlations between the immunoassay and the bioassays were significant and about 70% of the results were in the same categories whichever method was used. The use of the radioimmunoassay for the clinical assessment of pituitary—gonadal function is discussed.
ACUTE EFFECTS OF SYNTHETIC PORCINE CALCITONINS ON THE RENAL EXCRETION OF MAGNESIUM, INORGANIC PHOSPHATE, SODIUM AND POTASSIUM
Authors: NIELSEN S. PORS , BUCHANAN-LEE B. , MATTHEWS E. W. , MOSELEY J. M. , WILLIAMS C. C. 
Published: December 2008

SUMMARY
Synthetic porcine calcitonin (α-calcitonin) and its methionine-sulphoxide derivative (β-calcitonin) were given by intravenous infusion to conscious male rats. α-Calcitonin inactivated by performic acid oxidation was used as a control.
Microgram doses of α-calcitonin produced a dose-dependent decrease in the renal excretion of magnesium. The effect was not due to a secondary release of parathyroid hormone since it was also seen in parathyroidectomized animals.
A marked increase in the renal excretion of inorganic phosphate, sodium and potassium preceded the change in magnesium excretion in parathyroidectomized rats. It is concluded that the phosphaturia and natriuresis previously described after administration of extracted calcitonin preparations are true effects of the hormone.
The effect of β-calcitonin was indistinguishable from that of α-calcitonin.
EFFECTS OF TESTOSTERONE ON GLYCOSAMINOGLYCANS IN THE PROSTATE, SEMINAL VESICLES AND SALIVARY GLANDS OF THE RAT
Authors: KOFOED J. A. , HOUSSAY A. B. , TOCCI A. A. , CURBELO H. M. , GAMPER C. H. 
Published: December 2008

SUMMARY
The effects of castration, and of the daily administration of 100 or 300 μg testosterone propionate (TP) for 1 month to castrated animals, on the glycosaminoglycans of the ventral prostate, seminal vesicles and salivary glands, were studied in male white rats.
Castration produced atrophy of the ventral prostate and seminal vesicles together with increased concentration of uronic acid, and atrophy of the submaxillary glands together with decreased uronic acid concentration. The administration of TP to castrated animals produced opposite effects. No changes in weight or in uronic acid concentration were found in the parotid and retrolingual glands. Fractionation on cellulose microcolumns showed that the changes in uronic acid concentration were due to changes in fraction 1 (glycoproteins) in the submaxillary glands, in fractions 2 (hyaluronic acid) and 3 (heparitin sulphate) in the seminal vesicles, and in all the chromatographic fractions in the ventral prostate.
SITE OF DEHYDROEPIANDROSTERONE SULPHATE BIOSYNTHESIS IN THE ADRENAL GLAND OF THE PREVIABLE FOETUS
Authors: COOKE B. A. , TAYLOR PATRICIA D. 
Published: December 2008

SUMMARY
The localization of enzymes required for dehydroepiandrosterone sulphate (DHAS) biosynthesis from pregnenolone in human foetal adrenal glands was investigated using a microtechnique to obtain serial tissue sections through the glands.
Both zones of the adrenal glands converted pregnenolone to pregnenolone sulphate and to 17α-hydroxypregnenolone, dehydroepiandrosterone and their sulphates. A higher conversion to the steroid sulphates was found in the foetal compared with the adult zone tissue incubations. In two experiments, the highest conversion to DHAS occurred with tissue from the foetaladult border zone. The relative amounts of the steroids formed during incubation with whole gland homogenates were similar to those formed in the incubations of the foetal zone.
THE ESTIMATION OF PLASMA 11-DEOXYCORTICOSTERONE IN MAN USING GAS-LIQUID CHROMATOGRAPHY WITH ELECTRON CAPTURE DETECTION
Authors: WILSON A. , FRASER R. 
Published: December 2008

SUMMARY
A method of estimating the peripheral plasma concentration of 11-deoxycorticosterone (DOC) in man by means of gas-liquid chromatography with electron capture detection is described. Purification requirements for samples and chromatographic media have been simplified by the use of a detector bypass valve which reduces the risk of detector contamination. For this reason the method is relatively short. There was no measurable blank using either plasma from an adrenalectomized subject or water. The normal range was found to lie between 4·1 and 17·2 ng/100 ml (mean 9·8). Dexamethasone administration to one subject resulted in a subnormal plasma DOC concentration.
THE EFFECTS OF DEXAMETHASONE AND ANDROGENS ON SEXUAL RECEPTIVITY OF FEMALE RHESUS MONKEYS
Authors: EVERITT B. J. , HERBERT J. 
Published: December 2008

SUMMARY
The effect of dexamethasone, given either alone or together with testosterone propionate or androstenedione, was studied in nine female rhesus monkeys (paired with three males) by making quantitative observations on behaviour in the laboratory.
Dexamethasone (0·5 mg/kg/day) given to oestrogen-treated ovariectomized female monkeys made them sexually unreceptive, and there was an associated decline in the level of the male's mounting activity. Testosterone propionate (100 or 200 μg/day) reversed completely the effects of dexamethasone on sexual behaviour. Androstenedione (100, 200 or 400 μg/day) had similar, but less marked, effects whereas cortisol (10 mg/day) or progesterone (100, 200 or 500 μg/day) were ineffective. Treating a female with testosterone prevented dexamethasone from reducing sexual receptivity. Parallel determinations of urinary free cortisol showed that the dexamethasone had suppressed the secretory activity of the adrenal cortex. There were no consistent changes, under any treatment, in the females' vaginal epithelia, sexual skins or clitorides, or in their water or electrolyte metabolism.
These findings indicate that adrenal androgens regulate sexual receptivity in these female primates, probably by an action on the central nervous system.
A PERFUSED TELEOSTEAN GILL PREPARATION: VASCULAR ACTIONS OF NEUROHYPOPHYSIAL HORMONES AND CATECHOLAMINES
Authors: RANKIN J. C. , MAETZ J. 
Published: December 2008

SUMMARY
When isolated eel gills were perfused under conditions resembling, as closely as possible, those found in vivo and under constant pressure, neurohypophysial hormones decreased and catecholamines increased the rate of flow of perfusate, the latter response being mediated by β-adrenergic receptors. When the Ringer solution was not filtered before use, flow rates rapidly declined and 10−5 m-adrenaline or noradrenaline was required to maintain constant flow. Under these conditions, 10−14 m-isotocin or 10−13 m-arginine vasotocin (AVT) produced vasoconstriction. When the Ringer solution was filtered through a 0·22 μm Millipore filter before use, constant high flow rates could be maintained in the absence of catecholamines. Noradrenaline increased the flow rate at concentrations of down to 10−9 mol/l, adrenaline being slightly less active when filtered Ringer solution was used. However, the sensitivity to neurohypophysial hormones was considerably reduced, 10−11 to 10−10 m-isotocin and 5 × 10−11 to 5 × 10−10 m-AVT being the lowest concentrations producing vasoconstriction.
No difference in sensitivity to neurohypophysial hormones or catecholamines was observed between gills from seawater adapted or freshwater adapted gills. The results are discussed in relation to the alternative pathways of blood flow through the gills.
LIPID METABOLISM OF THE RAT UTERUS AFTER MATING
Authors: BEALL J. R. , WERTHESSEN N. T. 
Published: December 2008

SUMMARY
In this study of lipid metabolism of the rat uterus during early pregnancy, lipids were extracted after incubation with [1,2-14C]acetate or after its administration in vivo. The results indicated that the synthesis and concentration of triglyceride increased with time after mating. Triglyceride accumulated in uterine tissue before implantation and was depleted in tissue from implantation areas by day 7. Synthesis of fatty acid increased with time after mating, as did the concentration of various lipids other than cholesterol in the free sterol fraction. Supporting the concept that lipids are necessary during early embryonic development, the results suggest that the rat utilizes endometrial fatty acid esterified to triglyceride. No trends related to time were seen in the rate of synthesis nor in the concentration of sterol ester or free fatty acid; hence, specific concentrations of these lipids are probably not necessary for embryonic development during early pregnancy.