bluuebunny/crossref_metadata_2025_split huggingface dataset:
THE FIRST INTERNATIONAL STANDARD FOR GLUCAGON
Authors: Annable L. , Bangham D. R. , Salokangas A. Anneli , Storring P. L. 
Published: December 2008

ABSTRACT
The preparation and nature of the first International Standard for Glucagon are described. The glucagon activity of this material was compared with that of the U. S. P. Glucagon Reference Standard in a collaborative assay by 3 laboratories, in 3 different countries, who between them used 3 different methods. The results from all 29 valid assays obtained in this way gave homogeneous (1 % level) potency estimates and were combined to give a value of 1.49 U. S. P. glucagon units per ampoule with 95 % fiducial limits of 1.45–1.54. On the basis of the results obtained the material has been established as the first International Standard for Glucagon and allocated a potency of 1.49 International Units per ampoule. The International Unit for glucagon is thus defined as the activity contained in 4.53 mg of the first International Standard for Glucagon.
ACCUMULATION OF CYCLIC AMP IN HYPOTHYROIDISM. DECREASED SENSITIVITY TO NOREPINEPHRINE IN RAT ADIPOCYTES
Authors: Grill V. , Rosenqvist U. 
Published: December 2008

ABSTRACT
The effect of hypothyroidism on the noradrenaline-induced accumulation of 3H-cyclic-AMP was measured in rat epididymal adipose tissue. Adipocytes from hypothyroid animals showed a decreased response to noradrenaline 0.02−0.2 × 10−5 m, while higher concentrations of the catecholamine seemed to elicit the same response in cells obtained from euthyroid or hypothyroid animals. The diminished sensitivity to noradrenaline was unaltered after the addition of phentolamine. It is suggested that thyroid hormones modulate the catecholamine-induced lipolytic response at least partly through the adenyl cyclase cyclic-AMPN system.
GLUCOSE TOLERANCE IN NEWBORN INFANTS OF HEALTHY MOTHERS: ITS RELATIONSHIP TO THE MOTHERS' INSULIN RESPONSE TO GLUCOSE INFUSION
Authors: Edström Karin , Cerasi Erol , Luft Rolf , Persson Bengt , Thalme Berlil 
Published: December 2008

ABSTRACT
It has earlier been postulated that a low insulin response to a glucose infusion is characteristic for the prediabetic individual (Cerasi & Luft 1967c). There is also evidence that some infants of individuals with low insulin response might have a carbohydrate metabolism that is in some respects similar to that of newborn infants to diabetic mothers (Edström et al. 1974).
In the present study 15 infants to low insulin responders (ILR) and 22 infants to high insulin responders (IHR) were subjected to an intravenous glucose load (IVGTT) at 2–24 h age. A significant difference in glucose tolerance was found between the groups, the mean k-value for the ILR being 1.39 ± 0.41 and that for the IHR 1.05 ± 0.09 (P < 0.05).
No mothers were found to have a gestational diabetes (with the possible exception of one low insulin responders) but during late pregnancy the mean k-value at IVGTT in the low responders decreased from nonpregnant values (the mean difference being 0.41 ± 0.20, P < 0.025) while the high responders did not show a corresponding decrease (mean difference 0.12 ± 0.25, P > 0.05).
No other differences between the groups of infants that could influence the k-value could be found apart from the mothers being low or high insulin responders. Our findings show that a low insulin response in the mothers might affect the glucose tolerance of the foetus even in the absence of continuous maternal hyperglycaemia in late pregnancy.
SEASONAL PATTERNS OF SLEEP STAGES AND SECRETION OF CORTISOL AND GROWTH HORMONE DURING 24 HOUR PERIODS IN NORTHERN NORWAY
Authors: Weitzman Elliot D. , deGraaf Andries S. , Sassin Jon F. , Hansen Tomar , Godtlibsen Ole B. , Perlow Mark , Hellman Leon 
Published: December 2008

ABSTRACT
A group of 7 healthy male subjects was studied in regard to sleep stages and 24 h plasma cortisol and growth hormone patterns during the 4 seasons of the year in an Arctic environment (Tromsø, Norway). No difference in total sleep or sleep stage per cents was found for any of the yearly seasons. A small but statistical significant increase in mean plasma cortisol concentration and amount secreted for 24 h was found for the autumn-winter seasons, as compared with the spring and summer. However, no difference in the circadian curve of cortisol hormonal pattern was found. All subjects secreted growth hormone shortly after sleep onset at night and no difference was found as a function of season of the year.
FOLLICULAR AND LUTEAL FUNCTION IN THE PUBERAL RAT: GONADOTROPHIC HORMONE STIMULATION AND ENZYMIC-NUCLEOTIDE INTERACTIONS
Authors: Richards JoAnne S. (Hunter) 
Published: December 2008

ABSTRACT
Using the puberal rat and the PMS-treated rat as animal systems, ovarian events associated with follicular and luteal development have been characterized by measuring gonadotrophic hormone (LH, FSH and prolactin) and progesterone concentrations in peripheral serum; and selected enzymic (NAD-kinase:NAD-K and glucose-6-phosphate dehydrogenase: G6PD) activities and nucleotide (NAD, NADH, NADP, NADPH, ATP) concentrations in ovarian tissue.
In the puberal rat, the period of follicular development was characterized by increased ovarian NAD-K SA, NAD and NADH concentrations and decreased ATP and NADP concentrations. The first pro-oestrus was characterized by greatly elevated LH, FSH, prolactin and progesterone concentrations, significant decreases in ovarian NAD-K SA, NAD, NADP and ATP concentrations, and an increase in NADPH concentrations. The development of new corpora lutea was associated with striking increases in ovarian NAD-K SA and G6PD SA. Increased activity of both enzymes exhibited a significant positive coefficient of correlation with the number of corpora lutea contained within the ovarian tissue.
PMS (4 IU) stimulation of follicular activity resulted in events leading to the induction of an endogenous LH surge and ovulation. Associated with increased follicular activity was increased ovarian NAD-K SA. In contrast to the puberal rat, no rise in progesterone concentrations was associated with the LH surge or the formation of corpora lutea.
CORRELATION BETWEEN SOMATOMEDIN A IN SERUM AND BODY HEIGHT DEVELOPMENT IN HEALTHY CHILDREN AND CHILDREN WITH CERTAIN GROWTH DISTURBANCES
Authors: Hall Kerstin , Filipsson Rune 
Published: December 2008

ABSTRACT
The somatomedin A level in serum was determined in a series of 66 children in whom longitudinal data on body height growth and dental development were available. The series comprised normal children as well as children with some different types of growth disturbances. A high correlation was found between the somatomedin A level and the age at a certain stage of the dental maturity (r = −0.67) and between the somatomedin A level and the growth rate at this age (r = 0.67). The different groups of patients ranging from pituitary dwarfs to unusually tall children demonstrated a continuous gradient in the correlation between the level of somatomedin A and the different variables of the somatic development.
EFFECTS OF GENERAL ANAESTHESIA AND SEVERITY OF SURGICAL STRESS ON SERUM LH AND TESTOSTERONE IN MALES
Authors: Nakashima A. , Koshiyama K. , Uozumi T. , Monden Y. , Hamanaka Y. , Kurachi K. , Aono T. , Mizutani S. , Matsumoto K. 
Published: December 2008

ABSTRACT
Significantly decreased levels of serum testosterone from the pre-anaesthesia level were found during and up to 7 days following major surgery under general anaesthesia (nitrous oxide, oxygen and halothane following induction with thiopental and succinylcholine chloride) in 18 male patients. On the other hand, in the same patients, the serum luteinizing hormone (LH) increased significantly from the pre-anaesthesia level 30 min and 1 h after the beginning of anaesthesia. A slight increase in LH level was also noted on the 7th post-operative day. The determinations of serum testosterone and LH in fiberoptic bronchoscopy under the same general anaesthesia as that used in surgery or local anaesthesia in 26 male patients, revealed that the change in the serum LH during and following surgery seemed to be mainly induced by the general anaesthesia and that the rate of decrease in the serum testosterone may be related to the severity of surgical stress including the anaesthesia.
The rate of increase in serum testosterone following the injection of gonadotrophin in 20 males on the 6th post-operative day was similar to that in 10 pre-operative males. The effects of pulmonary lobectomy on serum testosterone and urinary steroids were also studied in 6 males under adrenal suppression with dexamethasone. On the 6th post-operative day, the urinary aetiocholanolone plus androsterone and serum testosterone were found to be half the level of those on the pre-operative day, while the urinary 5β-pregnane-3α,17α,20α-triol remained unchanged. These observations in human are not inconsistent with the report of Tcholakian & Eik-Nes (1971) in dogs namely that a shift in androgen biosynthetic pathway is present in the testis under surgical stress.
THE EXCHANGE OF THYROXINE BETWEEN PLASMA AND LIVER: THE ROLE OF FREE THYROXINE
Authors: Hillier A. P. 
Published: December 2008

ABSTRACT
An investigation has been made into the exchange of thyroxine between human plasma and the perfused rat liver. A stop-flow method was used to hold plasma within the liver sinusoids for periods up to 20 MIN. At 20°C it was found that thyroxine present in the sinusoids transferred to the liver at a rate of 5–6%/min; and that thyroxine transferred from the liver to the plasma at a rate of 1 %/min. In a second series of experiments, trace amounts of free thyroxine were injected into the stream of plasma just as it entered the tissue; the liver captured 18.5% of this injected hormone.
In the Discussion it is noted that 29 % of the plasma thyroxine dissociates into free solution each minute. If the liver is able to capture 18.5% of this hormone (as the above experiment suggests) then the plasma-to-liver transfer rate would be 5–6 %/min, which is the rate actually observed. These observations strongly suggest that the transfer of thyroxine from plasma to liver involves its initial release into the free state followed by trapping by the tissue binding sites.
THE POSTNATAL OCCURRENCE OF BIOGENIC MONOAMINES IN PANCREATIC ISLETS OF GOLDEN HAMSTERS
Authors: Cegrell Lennart 
Published: December 2008

ABSTRACT
Fluorescence histochemical studies in newborn and young golden hamster have revealed that some cells in the islets of Langerhans contain monoamine. These cells can be seen in newborns and up to ten day old animals, at least in three to five days old animals the amine behaves like dopamine and is mostly stored in the A2-cells.
ON THE MODULATING EFFECTS OF OVARIES ON NEONATAL ANDROGEN PROGRAMMING OF RAT LIVER ENZYMES
Authors: Stenberg Åke 
Published: December 2008

ABSTRACT
The metabolism of 4-[4-14C]androstene-3,17-dione in rat liver microsomal and cytosol fractions was investigated in adult female rats treated with 1.45 μmole of testosterone propionate at birth. The effects of ovariectomy at 14 and 43 days of age on neonatal testosterone imprinting of enzyme levels were studied. Animals spayed 14 days after birth showed a typical masculinized hepatic enzyme activity pattern with a decreased level of the 5α-reductase activity and increased levels of 5α-reductase, 16α-hydroxylase and 17α- and 3β-hydroxysteroid reductase levels. The pattern was essentially the same in testosterone propionate-treated rats spayed 43 days after birth – with the exception of a feminized 5α-reductase activity – whereas a completely feminized ("de-imprinted") pattern of enzyme activities was found in the rats with intact ovaries at the time of death. It is concluded that de-imprinting action of ovaries is mainly of a reversible nature.
HORMONE AND ENZYME ASSAYS IN PREGNANCY
Authors: Christensen Arne , Hagelid P. E. 
Published: December 2008

ABSTRACT
A rapid and simple method for determination of the placental cystineaminopeptidase (P-CAP) activity in plasma is presented. The enzymecatalysed hydrolysis of the substrate, l-cystine-bis-p-nitroanilide, is followed in a spectrophotometer by reading the absorbance of the product p-nitroaniline at 380 nm. The absorbance increases linearily with time after a lag-period of 30 seconds to 5 min. The reaction is followed for about 10 min. and the increase in absorbtion per min is calculated from the linear part of the absorbtion curve. The test could also be performed by taking 2 readings at about 5 min intervals.
In the studies of the enzyme kinetics a competitive inhibitor of the reaction was found in plasma. The amount of the inhibitory substances seemed to be nearly constant in the plasma samples studied from normal pregnant women as well as in plasma samples with high enzyme activity (twin-pregnancy) and low enzyme activity (severe pre-eclampsia).
The normal enzyme activity pattern showed an increase from about 210 days of pregnancy and towards the term. A coefficient of correlation of + 0.83 with the more time consuming method using l-cystine-di-βnaphtylamide as substrate was found. It was concluded that the present method could replace the method described by Babuna & Yenen (1966) at least from about 210 days of pregnancy and where a rapid answer is necessary.
THE MEASUREMENT OF HYPOTHALAMIC RELEASING HORMONE CONTENT AND ACTIVITY IN THE UNANAESTHETIZED RAT BY MEANS OF CAROTID ARTERY CANNULATION
Authors: Krause Robert , Syllwasschy-Anlauf Barbara 
Published: December 2008

ABSTRACT
To gain insights into quantitative changes in hypothalamic substances which affect the function of the anterior hypophyseal lobe, we developed a technique for carotid cannulation allowing sequential measurements of plasma levels of an affected hormone after injection of such a factor. The principle involves the use of a previously cannulated rat in an unanaesthetized unstressed condition The hypothalamic extract or LH-RH injected into the cannulas of such animals leads to rapid peaks of LH in peripheral blood removed from the same cannulas within 6 to 8 min, followed by a slow decrease. At least 50% of the peak value is usually found within 3 min. The technique yields quantitatively reproducible results, and appears suitable for measuring relative potencies of test extracts against pure standards and, within as yet undetermined limits, for kinetic studies.
ASSESSMENT OF GH RELEASING HORMONE ACTIVITY IN SEPHADEX-SEPARATED FRACTIONS OF PORCINE HYPOTHALAMIC EXTRACTS BY HYPOPHYSEAL PORTAL VESSEL INFUSION IN THE RAT
Authors: Takahara Jiro , Arimura Akira , Schally Andrew V. 
Published: December 2008

ABSTRACT
Growth hormone-releasing hormone (GH-RH) activity in Sephadex G-25 fractions of porcine stalk median eminence (SME) extracts was examined in vivo by infusing these samples into a rat hypophyseal portal vessel. The increment of immunoreactive GH levels in the serum was used as the index for GH-RH activity. The GH-RH activities were found in two different locations: in the early fractions Nos. 3–4, and in somewhat retarded fraction No. 7. These GH-RH activities were not due to TRH, vasopressin, or potassium. The location of LH releasing hormone (LH-RH) and prolactin release-inhibiting hormone (PR-IH) determined in this in vivo system was in agreement with those found in other in vivo and in vitro assay systems for LH-RH and PR-IH, respectively. These results help validate this assay system.
STUDIES ON THE INHIBITORY EFFECT OF SOMATOSTATIN ON GLUCOSE INDUCED INSULIN RELEASE IN THE ISOLATED PERFUSED RAT PANCREAS
Authors: Efendić S. , Luft R. 
Published: December 2008

ABSTRACT
Somatostatin, the recently discovered growth hormone release-inhibiting hormone in the hypothalamus, also inhibited glucose induced insulin release from the isolated perfused rat pancreas. The lowest effective dose of somatostatin was 1 ng/ml of perfusate. By increasing the dose to 100 ng/ml an almost complete inhibition of basal as well as stimulated insulin release was obtained. The inhibition of glucose stimulated insulin release mediated by somatostatin might be of competitive nature since somatostatin seemed to dislocate the glucose-insulin dose-response curve to the right.
STUDIES ON THE MECHANISM OF SOMATOSTATIN ACTION ON INSULIN RELEASE IN MAN
Authors: Efendić S. , Luft R. 
Published: December 2008

ABSTRACT
The present studies have demonstrated that the growth hormone release-inhibiting factor of the hypothalamus, somatostatin, exerts a prominent inhibiting action on glucose induced insulin release in man. This inhibition of insulin release could not be reversed by infusion of the α-adrenergic blocking agent, phentolamine. Our findings therefore suggest that the inhibiting effect of somatostatin on glucose induced insulin release is not mediated by the α-adrenergic receptors.
INSULIN COMPONENTS RELEASED BY THE NORMAL AND SUBTOTAL DEGRANULATED PERIFUSED ISLETS OF LANGERHANS OF THE RAT
Authors: Hermida O. García , Gómez-Acebo J. 
Published: December 2008

ABSTRACT
The insulin components released from normal and tolbutamide treated islets of the rat were studied in a perifusion system. The treated islets showed diminished quantities of insulin secreted as compared to the controls and an increase in the proportions of "big insulin" secreted during the second phase of this release. On the other hand, the main component of insulin released during the first phase was "little insulin". These studies confirm that the subtotally degranulated islets are less efficient than the controls in producing insulin release.
PROGESTERONE-BINDING PROTEINS: IN VITRO BINDING AND BIOLOGICAL ACTIVITY OF DIFFERENT STEROIDAL LIGANDS
Authors: Kontula Kimmo , Jänne Olli , Vihko Reijo , de Jager Evert , de Visser Jacob , Zeelen Filippus 
Published: December 2008

ABSTRACT
Progesterone-binding proteins from human, rabbit, sheep and guinea pig myometrial cytosol, all induced with oestradiol, as well as from pregnant guinea pig myometrium and plasma were investigated. The physico-chemical properties of the oestradiol-induced binding proteins were very similar in all the species studied.
In all, 63 steroids were tested for their ability to compete with tritiated progesterone for the binding sites on these six proteins and their relative affinities were determined. The studies reveal that the ligand specificities of oestrogen-induced myometrial binding proteins from human, rabbit and sheep are rather similar, whereas that from guinea pig myometrium has different binding characteristics. The properties of the binding proteins from pregnant guinea pig uterus and plasma differ substantially from all of the induced proteins. It is clear from the different physico-chemical characteristics and binding specificities that the oestrogen-induced myometrial protein of the guinea pig is not the same as that which appears in the myometrium and plasma during pregnancy.
The binding energies of the well bound progestational compounds were of the order of −12 Kcal/mole, half of which stems from the interaction of the steroid nucleus with the protein. The specific interaction of the protein with the two functional groups, the 3-keto-4-ene system and the acetyl side chain each contributed −3 Kcal/mole. In the case of the rabbit, sheep and human proteins a 17α-ethynyl-17β-hydroxyl function could replace the acetyl side chain.
For a large number of steroids reasonable agreement existed between the degree of binding to the rabbit myometrial protein and in vivo biological activity (Clauberg-McPhail test) in the same species. The data suggest that as far as the binding aspect is concerned, the rabbit is an appropriate model for assessing the biological activity of compounds under development for human application. The in vitro binding system is also a useful tool to assess whether steroids need to be bio-activated before eliciting a biological response.
PLASMA TESTOSTERONE IN KLINEFELTER'S SYNDROME: DIURNAL VARIATION AND RESPONSE TO ACTH AND DEXAMETHASONE
Authors: Smals A. G. H. , Kloppenborg P. W. C. , Benraad T. J. 
Published: December 2008

ABSTRACT
The mean basal plasma testosterone level in 28 patients with chromatin positive Klinefelter's syndrome was significantly lower than in 58 healthy male controls. In 12 of the patients the hormone levels were in the normal range. In both the eugonadal males and the Klinefelter patients the plasma testosterone levels spontaneously decreased throughout the day, the relative decrease in both groups being of the same order of magnitude.
Short term ACTH infusion and the administration of dexamethasone did not significantly influence the plasma testosterone concentration in the Klinefelter patients. These findings do not support the view that the adrenal cortex plays a major role in contributing to the circulating plasma testosterone levels in this syndrome.
THE PLASMA PROLACTIN LEVELS IN MAN DURING PROLONGATION OF DARKNESS IN THE MORNING
Authors: Osterman P. O. , Wide L. 
Published: December 2008

ABSTRACT
The plasma prolactin levels were studied in 4 healthy subjects with a constant sleep-waking cycle and a constant activity schedule before and after experimental alteration of the dark-light cycle. The subjects slept in the dark from 10.30 p. m. to 6.30 a. m. During a control period of 10 days the subjects stayed in rooms which were well lighted after 6.30 a. m. During the following 10 days darkness was prolonged by 4 hours until 10.30 a. m. Blood samples were obtained at 10.30 p. m., and each hour from 2.30 to 11.30 a. m. on days 9 and 10 of each period of investigation. In all the subjects an increase of the plasma prolactin level occurred during sleep. At about the time of waking the concentration fell rapidly. There was no apparent shift in the waking-related decrease in the prolactin level during the experimental period with extended darkness. Present data do not indicate that the dark-light transition in the morning is essential for the waking-related decrease in the prolactin level.
EFFECT OF OVARIECTOMY ON OESTROGEN-SENSITIVE FEEDBACK ELEMENTS
Authors: Zanisi M. , Martini L. 
Published: December 2008

ABSTRACT
Serum LH and FSH were measured by radioimmunoassay in untreated and oestrogen-treated ovariectomized rats. The animals were sacrificed 7, 14, 21 and 28 days after ovariectomy. Oestradiol benzoate was administered in the daily dose of 50 μg on the 2 days preceding sacrifice. It has been found that oestrogens exert a strong inhibitory effect on the release of LH, as evidenced by a decrease in serum titers of the hormone. Oestradiol suppressed LH almost completely in animals with both low (7 or 14 days post-ovariectomy), and high levels of serum LH (21 or 28 days post-ovariectomy). Oestradiol failed to totally suppress serum FSH at any post-castration time considered. Moreover, the inhibitory effect of oestradiol on FSH release decreased as post-castration time increased. These data suggest that the feedback mechanisms which control the secretion of LH and those which control the secretion of FSH are substantially different.
THYROXINE METABOLISM IN THE RAT: EFFECT OF VARYING DOSES OF EXOGENOUS THYROXINE
Authors: Galton Valerie Anne 
Published: December 2008

ABSTRACT
Experiments were performed to determine quantitatively the peripheral metabolism of exogenous thyroxine T4) in rats brought to isotopic equilibrium with doses of 131I-T4 ranging from 1 to 20 μg/100 g body weight/ day. It was found that, although the absolute amount of T4 either deiodinated and excreted as iodide in urine or excreted as T4 in faeces increased as the dose of T4 increased, the percentage of hormone excreted by either pathway at each dose level was relatively constant. In other words, the fractional rate of deiodination is not greatly influenced by the amount of T4 administered. A 20-fold increase in the dose of T4 resulted in only a 4-fold increase in serum T4 concentration measured 24 h after injection, but serum T4 levels were elevated considerably more than this for several hours between injections. Nevertheless, the highest dose of T4 was not greatly thyrotoxic. The implications of these findings in relation to the possible association between the metabolism and action of T4 are discussed.