bluuebunny/crossref_metadata_2025_split huggingface dataset:
Androgen receptor levels in patients with isolated hypospadias
Authors: Terakawa Tomoyoshi , Shima Hiroki , Yabumoto Hidenori , Koyama Koji , Ikoma Fumihiko 
Published: June 2009

Abstract.
The binding of [3H]dihydrotestosterone (17β-hydroxy-5α-androstan-3-one) to the androgen receptor was studied in 26 prepubertal boys with isolated hypospadias (no associated anomaly) using fibroblasts cultured from surgical specimens of hypospadiac penile skin and/or chordal tissue. Maximal binding capacities of androgen receptor for [3H] dihydrotestosterone in 10 patients with mild degree (2 glandular+8 penile), 6 with severe degree (4 penoscrotal + 2 scrotal), chordal tissues of hypospadias (N=10), and controls (10 endocrinologically normal boys) were, respectively, 11750±2410, 10720±2680, 16100±7570, and 11570±3830 (mean ± sd) sites per cell. Dissociation constants in these subjects were 1.09±0.29,0.93±0.22,1.20±0.31, and 1.22±0.41 × 10−10 mol/l respectively. There were no significant differences as to both maximal binding capacity and dissociation constant of androgen receptor among any groups. Abnormal receptor thermolability was not found in 5 patients with severe degree of hypospadias either. It is, therefore, concluded that prepubertal boys with isolated hypospadias have primarily normal androgen receptor activity.
Effect of prolonged overnight fasting on energy metabolism in non-insulin-dependent diabetic and non-diabetic subjects
Authors: Groop Leif C. , Bonadonna Riccardo , DelPrato Stefano , Ratheiser Klaus , DeFronzo Ralph A. 
Published: June 2009

Abstract.
The effect on energy metabolism of a 6-h prolongation of the conventional 12-h overnight fast was examined in 9 healthy subjects and in 7 patients with non-insulin-dependent diabetes mellitus. Plasma glucose concentration decreased by 7 and 23%, in control and diabetic subjects, respectively. In control subjects, the fall in plasma glucose was associated with a slight but significant fall in plasma insulin and a rise in plasma free fatty acid concentrations. During this same period, the rates of plasma free fatty acid oxidation, measured by infusion of [14C]palmitate, and net lipid oxidation, measured by indirect calorimetry, increased in normal subjects by 55 and 76%, respectively; the rate of glucose oxidation measured by indirect calorimetry decreased by 37%. In the diabetic patients, the free fatty acid oxidation rate was enhanced already after 12 h of fasting compared with controls (2.06 vs 1.30 μmol · kg−1 · min−1; p<0.05) and did not change significantly during the 6-h observation period. After 18 h of fasting, the rate of plasma free fatty acid oxidation was similar in control and diabetic subjects. The data thus emphasize the need for strict standardization of the overnight fasting period for metabolic studies, and demonstrate the difficulties in comparing basal rates of substrate oxidation between healthy and diabetic subjects.
Kallidin-induced stimulation of inositol phosphate production and prolactin release in rat anterior pituitary cells
Authors: Jones T. Hugh , Brown Barry L. , Dobson Pauline R. M. 
Published: June 2009

Abstract.
The effect of the kinin, kallidin (lysyl-brady-kinin) on phosphoinositide metabolism and prolactin secretion was examined in male rat anterior pituitary cells in primary culture. Kallidin was found to stimulate both total inositol phosphate production and prolactin release. The stimulation of inositol phosphate was biphasic in nature, similar to that previously reported for bradykinin, although kallidin was approximately 10-fold more potent. Kallidin also stimulated prolactin secretion provoking a maximal stimulation of 193.0±11.1 (sem)% at 1 μmol/l. These findings suggest that kallidin-induced prolactin secretion may be mediated intracellularly by activation of phosphoinositide metabolism. The B2 receptor antagonists had no significant inhibitory effects on kallidin-stimulated phosphoinositide metabolism or prolactin release. The B1 agonist des-Arg9-bradykinin has previously been shown to have no effect on either parameter. As the effects of kinins on anterior pituitary cells do not appear to be mediated by either of the known kinin receptors, they may, therefore, act via a hitherto unrecognised kinin receptor.
Circulating forms and biological activity of intact and truncated insulin-like growth factor I in adult and neonatal rats
Authors: Drakenberg Katarina , Östenson Claes-Göran , Sara Vicki 
Published: June 2009

Abstract.
A variant of IGF-I with a truncated aminoterminal region has been isolated and shown to display increased biological activity in vitro, but weak affinity of binding to the IGF binding proteins compared with intact IGF-I. In the present study, the circulating molecular forms and biological activity of intact and truncated IGF-I were compared after in vivo administration. Adult and 10-day-old rats were given 125I-truncated or 125I-intact IGF-I iv. In both adult and 10-day-old rats 125I-truncated IGF-I showed weaker affinity of binding to the IGF binding proteins and greater degradation than 125I-intact IGF-I. Serum half-life was 2 h for 125I-truncated IGF-I and 3 h for 125I-intact IGF-I in adult rats. The half-life in 10-day-old rats was 20.5 min for 125I-truncated IGF-I and 27 min for 125I-intact IGF-I. The uptake of 125I-truncated IGF-I into the kidney, liver and brain of 10-day-old rats was significantly higher than for 125I-intact IGF-I 15 min after iv administration. The insulin-like effects of the IGF-I peptides were examined in vitro and in vivo. Truncated IGF-I stimulated [3-3H]glucose incorporation into free fatty acids in adipocytes in vitro to a greater extent than did intact IGF-I. In vivo administration of both intact and truncated IGF-I to adult rats significantly decreased serum glucose levels and significantly increased the incorporation of [U-14C]glucose into glycogen. Thus, the present results demonstrated that truncated IGF-I displays reduced binding to the IGF binding proteins in vivo compared with intact IGF-I.
Triiodothyronine affects the electrical properties of GH3 cells
Authors: du Pont John S. 
Published: June 2009

Abstract.
Electrophysiological experiments show that T3 has a direct effect on the cell membrane of GH3 cells, a transformed line from the rat pituitary. Slope conductance versus membrane potential, resting membrane resistance, potential, capacity and action potentials were measured in this study. Using a current clamp technique, the effects of tetrodotoxin, tetraethylammonium, apamin, and nifedipine were measured and compared with those directly evoked by T3. T3 increased the slope conductance: 1. at around −60 mV, as did tetrodotoxin (Na+ channel blocker); 2. at about −40 mV, as did nifedipine (Ca2+ channel blocker), but decreased this conductance strongly between −20 and −30 mV, as did both nifedipine and apamin (Ca2+-sensitive K+ channel blocker). Action potentials were inhibited by T3 and by nifedipine. Action potentials in these cells are primarily related to Ca2+ ions. It seems that T3 inhibits the Ca2+ current and, as a consequence, the Ca2+-sensitive K+ current.
Gender-related differences of serum thyroxine-binding proteins in the rat
Authors: Emerson Charles H. , Cohen Joseph H. , Young Ruth A. , Alex Sharon , Fang Shih-Lieh 
Published: June 2009

Abstract.
Because little information is available, studies were performed to determine the relationship between gender and sex steroid status on serum T4 binding proteins in the rat. The binding capacity of serum thyroxinebinding globulin was greater in female rats than in male rats (27 ± 1.3 vs 18.0 ± 1.3 nmol/l, p<0.01) and in fasted female rats than in fasted male rats (64.4 ± 2.6 vs 30.8 ± 2.7 nmol/l, p<0.01). The binding capacity of serum transthyretin was lower in female rats than in male rats (2.1 ± 0.1 vs 3.1 ± 0.1 μmol/l, p < 0.01). Neither ovariectomy or orchidectomy affected the binding capacity of serum thyroxine-binding globulin and it was not increased in ovariectomized rats treated with estrogen. Orchidectomy did not cause a decrease in the binding capacity of serum transthyretin and testosterone administration did not increase it. In contrast, ovariectomy caused an increase in the binding capacity of serum transthyretin (Intact = 2.2 ± 0.1 vs ovariectomized = 2.8 ± 0.1 μmol/l, p <0.01) and estrogen administration caused a decrease (ovariectomized = 2.8 ± 0.1 vs ovariectomized + E2 = 1.9 ± 0.1 μmol/l, p <0.05). The results indicate that the binding capacity of serum thyroxine-binding globulin is higher in female rats than in male rats but this difference is not due to differences in the secretion of gonadal hormones. The binding capacity of transthyretin is lower in female rats than in male rats. This is probably due to the higher circulating levels of estrogen in the female compared to the male.
Thyroid status regulates particulate but not soluble TRH-degrading pyroglutamate aminopeptidase activity in the rat liver
Authors: Scharfmann Raphaël , Ebiou Jean-Claude , Morgat Jean-Louis , Aratan-Spire Sonia 
Published: June 2009

Abstract.
Rat liver contains two topologically different TRH-degrading pyroglutamate aminopeptidases. The particulate pyroglutamate aminopeptidase, unlike the soluble one, was highly specific for TRH and shared many physico-chemical properties with serum thyroliberinase, which is controlled by thyroid hormones. Both enzymes convert pGlu His Pro NH2 into His Pro NH2; the latter may be cyclized to cyclo His Pro known to possess several biological activities and specific binding sites in liver. The aim of the present study was to determine the effects of thyroid status on the particulate and soluble enzymes activity and gain more insight into their biological role. The regulatory pathway for the particulate pyroglutamate aminopeptidase was found similar to that of serum thyroliberinase: their specific activities decrease in hypothyroid rats and increase in hyperthyroid rats, whereas that of soluble enzyme remains unchanged. We postulate that the particulate pyroglutamate aminopeptidase may be a determining factor in the concentrations of TRH and/or cyclo His Pro reaching liver cells and a possible source for serum thyroliberinase. Taken together, these data suggest that this "converting enzyme" acts as a physiological regulator.
Hepatic lipase activity after liver denervation in hypothyroid rats
Authors: Berg Anna-Lena , Hammarström Lars-Erik , Hansson Per , Holmin Torsten , Nilsson-Ehle Peter 
Published: June 2009

Abstract.
Hepatic hilar denervation, hepatic vagotomy or sham operation were performed in hypothyroid rats. Activities of hepatic lipase were measured nine days after surgery. Sham operation in itself was associated with a decrease of hepatic lipase activity by about 40% compared with non-operated animals. Both hilar denervation and hepatic vagotomy were associated with increased hepatic lipase activity (40% and 35%, compared with sham-operated animals). Liver contents of norepinephrine were reduced by about 90% after hilar denervation, whereas hepatic vagotomy did not affect norepinephrine levels. No major changes in lipids and lipoproteins were noted.
T3 receptor occupancy and T3 levels in plasma and cytosol during rat brain development
Authors: Ferreiro Beatriz , Pastor Rosa , Bernal Juan 
Published: June 2009

Abstract.
The concentration and occupancy of the thyroid hormone receptor have been measured in rat brain nuclear extracts at the end of the fetal period and during the postnatal period. Receptor occupancy attained maximal values at postnatal day 15 (52% of total receptor binding sites occupied by T3) and correlated with plasma and cytosol total and free T3. The values for these parameters showed greater differences throughout development than did receptor occupancy. From gestational day 21 to postnatal day 15, total T3 increased in plasma from 0.18 to 1 nmol/l and in cytosol from 1 to 7.5 pmol/l. Free T3 increased in plasma from 1.2 to 6 pmol/l and in cytosol from 8 to 59 pmol/l. Nuclear free T3, calculated on the basis of receptor occupancy, and Kd increased in parallel, from 39.8 to 107 pmol/l at the same ages. Values for nuclear free T3 were between 2 and 5 times those in cytosol and between 10 and 40 times those in plasma, suggesting the presence of a small free T3 gradient from plasma to the nucleus. All of the above changes take place during the critical period of oligodendrocyte differentiation and the start of myelin gene expression, suggesting that thyroid hormone influences these important events of brain maturation.
Development of adrenomedullary function in suckling rats: Effects of high doses of thyroxine and cortisol
Authors: Goya L. , Aláez C. , Pascual-Leone A. M. 
Published: June 2009

Abstract.
The development of epinephrine, norephinephrine, and total catecholamine secretion in plasma and andrenal glands was studied in newborn rats at short intervals: at day 2, 4, 6, 8, 10, 12 and 23. The increase in the plasma level of epinephrine represents a maturation of the secretion of the adrenal medulla. The increase in plasma of epinephrine and norepinephrine and the content of catecholamines in the adrenal glands of both normal animals and those treated with either high doses of T4 or cortisol at birth suggest a slowing down of the normal development of epinephrine secretion. This was confirmed by inducing hypoglycemia in these three groups of animals by a 20-h fast or by insulin administration (0.1436 μmol/kg). We conclude that both high doses of T4 and cortisol administered at birth seem to retard the development of the autonomic nervous system similar to the effect on the central nervous system.
Cortisol release in pigs following peripheral and central administration of ovine and human corticotropin-releasing hormone
Authors: Parrott R. F. 
Published: June 2009

Abstract.
Prepubertal pigs (N = 6) were surgically implanted with iv and intracerebroventricular catheters. The animals were given oCRH or hCRH peripherally (0, 20 or 50 μg) or centrally (0, 10 or 20 μg) and the effect on plasma cortisol measured. Peak cortisol concentrations were observed 20 min after iv, and 40 min after intracerebroventricular, administration. A larger cortisol response was observed when 20 μg oCRH was given by the central, compared to the peripheral, route and intracerebroventricular administration of both 10 and 20 μg oCRH caused excitation and vocalisation. By contrast, the effect of hCRH on cortisol secretion was small, regardless of the route of administration, and only one animal displayed a behavioural response when the highest dose was given centrally.
Localization of renin substrate in fetoplacental tissue
Authors: Metsärinne Kaj P. , Pekonen Fredrika , Fyhrquist Frej Y. 
Published: June 2009

Abstract
Specific polyclonal rabbit anti-human renin substrate-antibodies were used in order to study the distribution of renin substrate immunoreactivity in human fetal and placental tissue. Renin substrate was immunohistochemically detected in human decidua and placenta, as well as in 19 weeks old human fetal liver and kidney. The presence of renin substrate in fetoplacental tissue supports the concept of a locally functioning renin-angiotensin system.
The mechanism for the discrepancy between serum total and free thyroxine values induced by autoantibodies: Report on two patients with Graves' disease
Authors: Iitaka Makoto I , Fukasawa Nobuhiko , Hara Yoshihito , Yanagisawa Morifumi , Hase Kazumasa , Miura Shiro , Sakatsume Yoshiki , Ishii Jun 
Published: June 2009

Abstract.
The sera from two patients with Graves' disease gave abnormally high serum free T4 values as compared with the total T4 and other hormone values, suggesting the presence of autoantibodies to labelled T4 analogue used in the Amersham free T4 assay kit. The autoantibodies appeared to develop after the initiation of methimazole therapy and disappeared again after the cessation of methimazole. This binding activity to labelled T4 analogue was demonstrated to be in the immunoglobulin G with a k light chain isotype in both sera, and was displaced by unlabelled T4 in a dose-dependent manner. The binding of immunoglobulin G purified from these sera to labelled T4 or T4 analogue was found to be almost identical to that of the corresponding serum binding. Since the specific radioactivity of labelled T4 analogue used in the Amersham free T4 assay kit is about 10 times higher than that of the labelled T4 in the Amersham total T4 assay kit, serum free T4 determinations are much more vulnerable to thyroid hormone autoantibodies. Thus, in the presence of autoantibodies, a large discrepancy develops between free T4 and total T4 values.
Endocrine, metabolic and cardiovascular responses to adrenaline after abdominal surgery
Authors: Hilsted J. , Wilken-Jensen C. , Birch K. , Nielsen M. Damkjær , Holst J. J. , Kehlet H. 
Published: June 2009

Abstract.
Adrenaline-induced changes in heart rate, blood pressure, plasma adrenaline and noradrenaline, cortisol, glucagon, insulin, cAMP, glucose, lactate, glycerol and β-hydroxybutyrate were studied preoperatively and 4 and 24 h after skin incision in 8 patients undergoing elective cholecystectomy. Late postoperative responses of blood glucose, plasma cAMP, lactate and glycerol to adrenaline infusion were reduced, whereas other responses were unaffected. Blood glucose appearance and disappearance rate as assessed by [3H]3-glucose infusion was unchanged pre- and postoperatively. The increase in glucose appearance rate following adrenaline was similar pre- and postoperatively. These findings suggest that several β-receptor-mediated responses to adrenaline are reduced after abdominal surgery.
Analysis of the gonadotropin surges in patients with premature ovarian failure undergoing steroid replacement cycles
Authors: Pellicer Antonio , Matallin Pilar , Valldecabres Maria C. , Miró Fernando , Remohi José 
Published: June 2009

Abstract
Ovarian steroids regulate pituitary gonadotropin secretion in normal cycles. This regulation has also been demonstrated in hypogonadal women receiving exogenous drugs, and has been suggested in women with premature ovarian failure receiving cycles of steroid replacement for oocyte donation. The purpose of this study was to analyse the gonadotropin surges in patients with premature ovarian failure using different experimental protocols. Those protocols were planned to induce the surges with different combinations of estradiol valerate and progesterone. According to the first protocol, a typical sequencial administration of estradiol valerate and progesterone was given as a control. Maximal estradiol levels were detected on day 12 of the artificial cycle. The negative feed-back of estradiol was evident, with a significant (p<0.05) reduction of FSH and LH from the initial values. The positive feed-back showed a moderate LH surge in 6 out of 8 patients. In addition, a mild FSH increase was detected in 4 women. Both surges occurred on day 15 and were coincident with a decreased estradiol valerate and increased progesterone intake. A second protocol was scheduled for 5 patients in order to identify a real LH surge. High-dose estradiol valerate administration was maintained and progesterone was not administered. The LH surge clearly appeared on day 15 in all subjects, but the peak value was again moderate. The third protocol was designed in order to demonstrate a real FSH surge in 4 patients. Progesterone administration was advanced by 5 days. This trial showed a mild FSH surge, which was advanced together with progesterone administration. These data demonstrate that women receiving artificial cycles for oocyte donation have an LH surge 3 days after maximal estradiol levels are achieved. No real FSH surge is demonstrable.
Thyroid hormones and thermogenesis: A microcalorimetric study of overall cell metabolism in lymphocytes from patients with different degrees of thyroid dysfunction
Authors: Valdemarsson Stig , Ikomi-Kumm Julie , Monti Mario 
Published: June 2009

Abstract.
We used microcalorimetry to measure lymphocyte heat production rate in patients with clinical and laboratoy hyperthyroidism (serum TSH ↓, serum FT4 ↑, serum FT3 ↑ ), subclinical hyperthyroidism (serum TSH ↓, serum FT4 ↑, serum FT3=), and subclinical hypothyroidism (serum TSH ↑, serum FT4 ↓, serum FT3=) compared with healthy controls (N= 13). The lymphocyte heat production rate was significantly correlated to the free thyroxine level (r=0.53, p<0.01) and to the free triiodothyronine level (r=0.51, p<0.01) when calculated from pooled data for the three patients groups. The hyperthyroid patients (N = 8) had a significantly increased lymphocyte heat production rate, 3.43±0.25 pW/cell, as compared with 2.31±0.12 pW/cell in the control group (p<0.001). The groups with subclinical hyperthyroidism (N = 7) and subclinical hypothyroidism (N=9) had lymphocyte heat production rates of 2.14±0.11 and 2.56±0.15 pW/cell, respectively, not significantly different from that in the controls. Consistently, there was no significant difference between patients with subclinical hyperthyroidism (N=5) and controls (N=5) with regard to lymphocyte energy production as calculated from separately measured oxygen comsumption rates in vitro, 1.36±0.20 and 1.56±0.12 pW/cell, respectively. Thus microcalorimetry seems to be suitable for studying the influence of thyroid hormones on cellular metabolism. Subclinical thyroid dysfunction does not seem to alter the overall rate of lymphocyte metabolism.
Between-lot variability in chromatographic and biochemical properties of hMG
Authors: Stone Bronte A. , Quinn Patrick , Marrs Richard P. 
Published: June 2009

Abstract.
Ten lots of dissociated hMG were characterized by reverse-phase gradient high-performance liquid chromatography. Areas of 12 discrete peaks were directly related to dosages of hMG injected. The lots were further analysed for immunoactive-FSH (41.6-106.2 IU/ampule), immunoactive-LH (11.0-20.4 IU/ampule), bioactive-LH (2.7-17.1 IU/ampule) and bioactive-hMG (149-298 pg E2/mIU immunoactive-FSH/ml). Relationships between integrated areas of the HPLC peaks and biochemical properties of the hMG lots were analysed by stepwise multiple linear regression. Between-lot differences in immunoactive-LH and immunoactive-FSH were related to HPLC peak areas (p<0.05); differences in bioactive-LH were not. Areas of 8 peaks were related to differences in bioactive-hMG activity, facilitating close approximation of bioactive-hMG from the derived multi-linear model (p<0.001). Rapid characterization of hMG by HPLC is of relevance as recent reports have shown that ovarian responses and pregnancy outcomes of patients are related to the immunoactive and bioactive gonadotropin content of hMG preparations used to induce multiple folliculogenesis before oocyte aspiration, in vitro fertilization, and embryo replacement.