bluuebunny/crossref_metadata_2025_split huggingface dataset:
Estradiol regulation of mRNA expression of stimulatory G-protein α-subunit in white adipose tissue from female rats
Authors: De Pergola Giovanni , Xu Xuefan , Carlsson Björn , Eriksson Peter , Edén Staffan , Giorgino Riccardo , Björntorp Per 
Published: December 2008

De Pergola G, Xu X, Carlsson B, Eriksson P, Edén S, Giorgino R, Björntorp P. Estradiol regulation of mRNA expression of stimulatory α-subunit in white adipose tissue from female rats. Eur J Endocrinol 1994;130:146–50. ISSN 0804–4643
Adipose tissue has been recognized as a major peripheral metabolic target of estrogens. The present study was addressed to examine in female rats whether differences in the adipose tissue mRNA expression of α-subunit of stimulatory (Gs) and/or inhibitory (Gj) G-proteins exist between intact and ovariectomized rats, the latter with or without estradiol or testosterone treatment. The fat cell membrane protein amount of Gs and Gj α-subunit also was examined. All these parameters were evaluated in parametrial fat tissue samples obtained from 40 female Sprague-Dawley rats. A group of rats (N=20) was investigated for evaluation of mRNA expression and another group (N=20) for quantification of the protein amount of Gs and Gj α-subunit. Each group was represented by five control rats (sham-operated), five ovariectomized (OVX) rats, five ovariectomized rats treated with estradiol (OVXE) and five ovariectomized rats treated with testosterone (OVXT). Ribonucleic acid extracted from adipose tissue and analyzed by northern blot with Gαs, Gαi-1 and Gαi-2 cRNA probes revealed three major bands with estimated sizes of 1.9, 3.5 and 2.35 kb, respectively. Messenger RNA quantitative analysis, by a solution of hybridization RNAase protection assay on total nucleic acid samples, showed that the amount of Gαi-1 and Gαi-2 mRNA was similar within the different groups, whereas the Gαs mRNA was significantly less abundant (p <0.01) in OVX and OVXT rats than in control or OVXE rats. No difference in Gαs mRNA content was found between control and OVXE rats. As with mRNA analysis, protein quantitative analysis by an enzyme-linked immunosorbent assay in fat cell membrane preparation showed that the amount of Gαi(1–2) was similar within the different groups and that the Gαs content was significantly higher in control and OVXE rats than in OVX and OVXT rats (p<0.01). This study in female rats shows that estradiol may be involved in the control of protein amount and mRNA expression of Gs α-subunit in adipose tissue. These results may explain in part how estrogens regulate the variations of body fat mass in female rats.
Giovanni De Pergola, via Putignani 236, 70122 Bari, Italy
Progesterone stimulates fibronectin production by chicken granulosa cells in vitro
Authors: Asem Elikplimi K , Conkright Michael D , Novero Ruben P 
Published: December 2008

Asem EK, Conkright MD, Novero RP. Progesterone stimulates fibronectin production by chicken granulosa cells in vitro. Eur J Endocrinol 1994;130:159–65. ISSN 0804–4643
Experiments were conducted in vitro to examine the effect of progesterone on fibronectin production by chicken ovarian granulosa cells. Granulosa cells isolated from the largest (F1: mature) and third-largest (F3: developing) preovulatory follicles as well as from a pool of immature small yellow follicles (SYF) of the domestic chicken ovary were incubated in serum-free Medium-199 and the amounts of fibronectin and progesterone produced were quantified by enzyme-linked immunosorbent assay and radioimmunoassay, respectively. The amounts of basal fibronectin and progesterone produced by granulosa cells from F1, F3 and SYF follicles increased with advancing stages of follicular development. Thus, the quantity of basal fibronectin secreted by granulosa cells was directly proportional to the amount of progesterone produced by them. Exogenously supplied progesterone increased the amount of fibronectin secreted by F1 and F3 cells in a dose-dependent manner, but its effect on SYF cells was marginal. Cyanoketone (an inhibitor of progesterone synthesis) suppressed basal fibronectin production by F1 and F3 granulosa cells and its inhibitory action was reversed by exogenous progesterone. The progesterone antagonist RU 486 also attenuated basal fibronectin production by F1 and F3 granulosa cells, but only the highest concentration affected SYF cells. The inhibitory effect of RU 486 was diminished in the presence of exogenous progesterone. These data show that progesterone regulates fibronectin production by chicken granulosa cells. They suggest that in avian granulosa cells, endogenous progesterone can stimulate fibronectin synthesis in an intracrine or autocrine manner.
EK Asem, Department of Physiology and Pharmacology, School of Veterinary Medicine, Purdue University, 1246 Lynn Hall, West Lafayette, IN 47907-1246. USA
l-Triiodothyronine acutely increases Ca2+ uptake in the isolated, perfused rat heart. Changes in l-type Ca2+ channels and β-receptors during short- and long-term hyper- and hypothyroidism
Authors: Gøtzsche Liv Bjørn-Hansen 
Published: December 2008

Gøtzsche LB-H. l-Triiodothyronine acutely increases Ca2+ uptake in the isolated, perfused rat heart. Changes in l-type Ca2+ channels and β-receptors during short- and long-term hyper- and hypothyroidism. Eur J Endocrinol 1994;130:171–9. ISSN 0804–4643
Acutely administered triiodothyronine (T3) in supraphysiological doses has been shown to exert an acute positive inotropic effect in vivo a few minutes after intravenous administration. To investigate whether this effect could be explained by an acutely increased Ca2+ uptake in the myocardium, an isolated perfused rat heart model ad modum Langendorff was established. The acute stimulative effect of T3 on myocardial Ca2+ uptake was determined indirectly by measuring changes in Ca2+ concentration in the perfusate following coronary perfusion with 45Ca2+-containing buffer. Perfusion with T3 gave rise to dose-dependent reductions in perfusate Ca2+ within 20 s. Following 10−9 and 10−11 mol/l T3, the effect was small and usually lasted less than 1 min. Perfusion with 10−6 and 10−7 mmol/l T3 resulted in a decrease in perfusate Ca2+, which remained stable throughout 4–6 min of observation. Calcium channel blockade with nifedipine prevented the decrease in perfusate Ca2 +, suggesting that voltage-operated Ca2+ channels are involved in the increased Ca2 + uptake. A washout period with T3-free buffer re-established the Ca2+ concentration in the perfusate, suggesting that the effect is reversible. Calcium channels have been suggested to be regulated directly by T3. Maximum binding capacities for myocardial Ca2+ channels and β-receptors were determined by binding studies with [3H]PN200-110 and [125I]iodocyanopindolol in short-term and long-term hyper- and hypothyroid rats. After 2 and 8 weeks, Ca2+-channel maximum binding capacities were reduced by 25% and 23% in hyperthyroid rats (p<0.05) and increased by 33% and 23% in hypothyroid rats (p<0.05). β-Receptor binding capacities were increased by 33% and 50% in hyperthyroid rats (p<0.05) and reduced by 28% and 47% (p<0.05) in hypothyroid rats. The reduced Ca2+-channel maximum binding capacity during chronic hyperthyroidism is hypothesized to be a secondary event to a T3-induced increase in myocardial Ca2+ uptake in hyperthyroid rats, serving a protective role against Ca2+ overloading of the cell. The acute increase in Ca2+ uptake following T3 administration may explain the reported acute inotropic effect of T3.
Liv Bjørn-Hansen Gøtzsche, Medical Department (Diabetes and Endocrinology), Århus Kommunehospital, University Hospital of Århus, DK-8000 Århus C, Denmark
Effect of P1-purinergic agonist on thyrotropin stimulation of H2O2 generation in FRTL-5 and porcine thyroid cells
Authors: Björkman Ulla , Ekholm Ragnar 
Published: December 2008

Björkman U, Ekholm R. Effect of P1-purinergic agonist on thyrotropin stimulation of H2O2 generation in FRTL-5 and porcine thyroid cells. Eur J Endocrinol 1994;130:180–6. ISSN 0804–4643
Our previous studies have shown that the generation of H2O2 in FRTL-5 thyroid cells is regulated via both the adenylate cyclase/cyclic adenosine monophosphate (cAMP) and Ca2+/phosphatidylinositol pathway: thyrotropin (TSH) stimulates H2O2 generation through both pathways, via the former at a low concentration and via the latter at a high concentration. In porcine thyrocytes in primary culture H2O2 generation is stimulated only via the Ca2+/phosphatidylinositol route. In the present study we explored the effect of a P1-purinergic agonist (phenylisopropyladenosine, PIA) on stimulations induced by TSH and by adenosine triphosphate (ATP), an activator of the Ca2+/phosphatidylinositol cascade via the P2-purinergic receptor. In FRTL- 5 cells, PIA potentiated H2O2 generation stimulated by TSH at 10U/l (but not at 1 U/l), Ca2+ mobilization induced by TSH and Ca2+ mobilization induced by ATP at 1 μmol/l (but not 10 μmol/l). Phenylisopropyladenosine strongly inhibited TSH-induced cAMP accumulation in FRTL-5 cells. In pig thyrocytes, PIA had no effect on H2O2 generation stimulated by TSH or ATP and no effect on ATP-stimulated Ca2+ mobilization. Also, PIA did not inhibit TSH-stimulated cAMP accumulation in pig thyrocytes, and by itselfhad no effecton H2O2 generation or Ca2 + mobilization. Thus, in FRTL-5 cells, but not in porcine thyrocytes, PIA modulates TSH-stimulated H2O2 generation by enhancing the Ca2+/phosphatitylinositol route and inhibiting the adenylate cyclase/cAMP route of the TSH signal. The net result of this modulation apparently depends on the balance between inhibition of the cAMP route and enhancement of the Ca2+ route. This may explain the lack of potentiation observed by 1 U/1 TSH.
Ragnar Ekholm, Department of Anatomy, Medicinaregatan 3, S-413 90 Göteborg, Sweden
Enhanced cell proliferation by hyperprolactinemia in both exocrine and endocrine pancreas in mice
Authors: Matsuda Manabu , Mori Takao , Park Min K , Yanaihara Noboru , Kawashima Seiichiro 
Published: December 2008

Matsuda M, Mori T, Park MK, Yanaihara N, Kawashima S. Enhanced cell proliferation by hyperprolactinemia in both exocrine and endocrine pancreas in mice. Eur J Endocrinol 1994;130:187–94. ISSN 0804–4643
Effects of hyperprolactinemia induced by ectopic anterior pituitary grafting on the pancreas were studied in male SHN mice. After pituitary grafting, the weight of pancreas rapidly increased. A similar increase in pancreatic weight was observed during lactation, a condition associated with elevated prolactin levels. Results of DNA and protein assays revealed that the increase in pancreatic weight in both pituitary-grafted and lactating mice was mainly due to the increase in the cell number, because the total DNA content per pancreas was greater in these mice than the controls. An increase in fluid volume or hypertrophy of cells also contributes to the weight increase; in contrast, the DNA and protein contents per unit tissue weight decrease. The rate of DNA synthesis determined by 5-bromo-2′-deoxyuridine labeling was higher both in acinar cells and islet B cells in pituitary-grafted mice han in the controls. Thus, hyperprolactinemia stimulates cell proliferation in exocrine pancreas as well as endocrine islets. The effect of prolactin seems to be indirect on acinar cells, because only B cells showed prolactin immunoreactivity in the mouse pancreas. In addition, insulin might not be a mediator of the prolactin effect on acinar cells, because the serum insulin level in pituitary-grafted mice failed to show any change.
Manabu Matsuda, Zoological Institute, School of Science, University of Tokyo, Bunkyo-ku, Tokyo 113, Japan
Low cord blood levels of catecholamine from a newborn of a pheochromocytoma patient
Authors: Dahia Patricia LM , Hayashida César Y , Strunz Célia , Abelin Neusa , Toledo Sérgio PA 
Published: December 2008

Dahia PLM, Hayashida CY, Strunz C, Abelin N, Toledo SPA. Low cord blood levels of catecholamine from a newborn of a pheochromocytoma patient. Eur J Endocrinol 1994;130:217–19. ISSN 0804–4643
Association of pheochromocytoma and pregnancy is rare and usually related to high maternal and fetal mortality rates. Maternal effects of the tumor have been studied extensively and the clinical outcome has markedly improved during the last decade. However, the role of excess catecholamines on fetal development has been discussed very little. We report here a case of pheochromocytoma during pregnancy, in which catecholamine levels from the cord blood were low despite simultaneous elevated maternal values (1.93 and 29.46 nmol/l norepinephrine, respectively), possibly owing to the high activity of the catecholamine degradative enzymes monoamine oxidase and COMT at the placental level. We suggest that in pregnancies complicated by pheochromocytoma, fetal well-being may be related mainly to good control of maternal blood pressure instead of to the amount of catecholamines in the fetal circulation, because the placenta performs a protective role through an effective process of hormone inactivation.
Patricia LM Dahia, Endocrine Genetics Unit, University of ã Paulo School of Medicine, 455 Dr. Arnaldo Ave, 4th Floor, Room 50, 01246–913 São Paulo, Brazil
Three years of growth hormone treatment in growth hormone-deficient adults: near normalization of body composition and physical performance
Authors: Jørgensen Jens OL , Thuesen Leif , Müller Jørn , Ovesen Per , Skakkebæk Niels E , Christiansen Jens S 
Published: December 2008

Jørgensen JOL, Thuesen L, Müller J, Ovesen P, Skakkebæk NE, Christiansen JS. Three years of growth hormone treatment in growth hormone-deficient adults: near normalization of body composition and physical performance. Eur J Endocrinol 1994;130:224–8. ISSN 0804–4643
Growth hormone (GH) replacement therapy in several controlled short-term trials have shown unanimous beneficial effects on body composition and other features. To evaluate more long-term effects we report data from 3 years of uninterrupted GH therapy in 10 GH-deficient adults who had all completed a previous double-blind placebo-controlled study and who also had been studied after 16 months of open GH therapy. No further increase in linear height was observed. The initial increase in thigh muscle volume was maintained after 3 years of GH therapy. A slight increase in body weight and thigh fat volume was recorded. Exercise capacity and isometric muscle strength were increased significantly compared to the initial placebo period. This was associated with stabilized levels of resting heart rate and blood pressure. Glycosylated hemoglobin levels were normal and did not change during the study. A standard oral glucose tolerance test performed at the end of the study revealed no evidence of glucose intolerance. No side-effects were reported. Compared to an age- and sex-matched group of healthy untreated subjects, thigh muscle volume, exercise capacity and isometric muscle strength had become normalized from subnormal levels after 3 years of GH therapy. We conclude that long-term GH replacement therapy in GH-deficient adults is associated with preserved beneficial effects on body composition and physical performance, resulting in a near normalization of several previously abnormal features and adding new merits to this treatment modality.
Jens OL Jørgensen, Medical Department M (Endocrinology and Diabetes), Aarhus Kommunehospital, DK-8000C, Denmark
No changes of insulin sensitivity in cystic fibrosis patients with different degrees of glucose tolerance: an epidemiological and longitudinal study
Authors: Cucinotta Domenico , De Luca Filippo , Gigante Alfonso , Arrigo Teresa , Benedetto Antonino Di , Tedeschi Antonino , Lombardo Fortunato , Romano Giacomo , Sferlazzas Concetta 
Published: December 2008

Cucinotta D, De Luca F, Gigante A, Arrigo T, Di Benedetto A, Tedeschi A, Lombardo F, Romano G, Sferlazzas C. No changes of insulin sensitivity in cystic fibrosis patients with different degrees of glucose tolerance: an epidemiological and longitudinal study. Eur J Endocrinol 1994;130:253–8. ISSN 0804–4643
Plasma glucose and insulin responses to oral glucose and insulin sensitivity by the euglycemic hyperinsulinemic clamp technique were investigated in 30 cystic fibrosis patients with normal fasting blood glucose levels and normal (N = 12), impaired (N = 12) or diabetic (N = 6) glucose tolerance, and in 12 control subjects. In a subgroup of 10 cystic fibrosis patients with non-diabetic glucose tolerance both oral glucose tolerance test and clamp were performed again 48–52 months later. Following oral glucose, glycemic responses were higher in cystic fibrosis patients than in controls, whereas insulin responses were reduced significantly only in the patients with diabetic glucose tolerance. Insulin sensitivity did not differ significantly in the patient subgroups with different degrees of glucose tolerance and in controls. In the 10 patients who underwent a 4-year follow-up, insulin responses to oral glucose decreased significantly, whilst insulin sensitivity did not change substantially. Insulin sensitivity persisted unmodified even in the patients with deteriorating glucose tolerance. No correlations were observed between metabolic data and clinical status of patients. In conclusion, in cystic fibrosis subjects with fasting euglycemia and different degrees of glucose tolerance: (i) insulin sensitivity is not impaired; (ii) eventual changes of glucose tolerance over time are not associated with modifications of insulin sensitivity; (iii) insulin secretion deteriorates over time even in the patients with stable glucose tolerance; (iv) eventual deterioration of both glucose tolerance and insulin secretion is not linked to a worsening of either nutritional or clinical parameters.
F De Luca, Istituto di Clinica Pediatrica, Policlinico Universitario, 98100 Messina, Italy
Estradiol and progesterone production by cultured granulosa cells cryopreserved from in vitro fertilization patients
Authors: Sluss Patrick M , Lee Kan-ei , Mattox John H , Smith Patricia C , Graham Margaret C , Partridge Ann B 
Published: December 2008

Sluss PM, Lee K, Mattox JH, Smith PC, Graham MC, Partridge AB. Estradiol and progesterone production by cultured granulosa cells cryopreserved from in vitro fertilization patients. Eur J Endocrinol 1994;130:259–64. ISSN 0804–4643
Gonadotropin-stimulated steroidogenesis was studied in cultured human granulosa-lutein cells obtained from patients undergoing procedures for in vitro fertilization. The impact of cryopreservation on cell function in vitro was studied. Granulosa cells obtained from in vitro fertilization patients were cultured in serum-supplemented medium or cryopreserved at −135°C for 2–22 months. Fresh (unfrozen) cells (105) produced estradiol at a rate of 1320 pmol/l (over 72 h) and progesterone at about 2500 nmol/l. Estradiol production by either fresh or cryopreserved granulosa cells in culture was unaffected by physiological concentrations of follicle-stimulating hormone (7IU/l). Adding testosterone (10−7 mol/l) to the medium increased estradiol secretion approximately sixfold. In contrast, progesterone production was not affected by follicle-stimulating hormone or testosterone. No significant differences were observed in cultures of cryopreserved granulosa cells compared to cultures of unfrozen cells with respect to estradiol secretion, the effects of follicle-stimulating hormone or testosterone on estradiol secretion, or progesterone production. Progesterone production by fresh and cryopreserved cells was stimulated by human chorionic gonadotropin. These data indicate that cryopreservation offers the potential to facilitate prospective studies utilizing large numbers of human granulosa-lutein cells in culture.
Patrick M Sluss, Reproductive Endocrine Unit, Massachusetts General Hospital East, 149 13th Street, Charlestown, MA 02129, USA
Regulation of parathyroid hormone gene expression and peptide secretion in human parathyroid cells
Authors: Liu Jianqi , Kahri Arvi I , Teppo Anna-Maija , Voutilainen Raimo 
Published: December 2008

Liu J, Kahri AI, Teppo A-M, Voutilainen R. Regulation of parathyroid hormone gene expression and peptide secretion in human parathyroid cells. Eur J Endocrinol 1994;130:394–401. ISSN 0804–4643
In cell cultures prepared from human parathyroid adenomas, parathyroid hormone (PTH) mRNA expression decreased slowly. During short-term incubations (less than 24), a low calcium concentration (0.5 mmol/l) and protein kinase C activator TPA (12-O-tetradecanoyl phorbol 13-acetate) (160 nmol/l) increased PTH secretion (60%; p <0.05), while a high extracellular calcium concentration (2.5 mmol/l) reduced PTH secretion (60%; p<0.05), The TPA could block the inhibitory effect of a high calcium level on PTH peptide secretion. All these agents had no effect on PTH mRNA accumulation in short-term experiments. In long-term cultures (more than 24 h), a low calcium level increased and a high calcium level reduced both PTH mRNA (85 and 34%; p <0.05) and peptide secretion (140 and 80%; p <0.05), respectively. The TPA reduced PTH mRNA accumulation down to 30% (p<0.05) and PTH secretion down to 14% (p<0.05) in a time- and dose-dependent fashion. The TPA also reversed the stimulatory effect of hypocalcemia on PTH mRNA accumulation and peptide secretion. Protein kinase C inhibitors staurosporine (100 nmol/l) and H-7 (1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride) (50 μmol/l) had similar effects to TPA on PTH gene expression and peptide secretion in long-term cultures. The results support the hypothesis that extracellular calcium regulates PTH mRNA accumulation and PTH secretion via protein kinase C.
Raimo Voutilainen, Department of Pathology, PO Box 21 (Haartmaninkatu 3), SF-00014 University of Helsinki, Finland
Subterranean mole-rats naturally have an impoverished calciol status, yet synthesize calciol metabolites and calbindins
Authors: Buffenstein Rochelle , Jarvis Jennifer UM , Opperman Lynne A , Cavaleros Meropi , Ross Frederick P , Pettifor John M 
Published: December 2008

Buffenstein R, Jarvis JUM, Opperman LA, Cavaleros M, Ross FP, Pettifor JM. Subterranean mole-rats naturally have an impoverished calciol status, yet synthesize calciol metabolites and calbindins. Eur J Endocrinol 1994;130:402–9. ISSN 0804–4643
Mole-rats (Family Bathyergidae) have no obvious source of calciol. They live in an environment devoid of sunlight and consume a herbivorous diet. Calciol status, metabolism and expression were examined in six species of Bathyergids. Serum levels of calcidiol in all species were < 5μg/l and those of calcitriol were low (18.0 ± 11.0 (sd) ng/l, N = 57) when compared to other rodents. Within 72 h of injecting animals with tritium-labelled calciol, most of the labelled prohormone had been metabolized to more polar metabolites. Three times more tritium-labelled calcitriol (19.3 ± 2.9%) was present than (24R)-hydroxycalcidiol (6.2 ± 10%). The natural absence of detectable circulating concentrations of calcidiol and the threefold greater amount of calcitriol to (24R)-hydroxycalcidiol produced indicate that calciol naturally is in short supply. Calciol-dependent calbindins were absent in the duodenum. Calbindin-D28k was present in the Purkinje cells of the cerebellum and in some collecting ducts and proximal and distal convoluted tubules of the kidney. Calbindin-D9k also was present but was localized uniquely in the juxtaglomerular cells of the five southern African species. These data confirm that Bathyergid mole-rats naturally have an impoverished calciol status. Despite the presence of calbindins in renal tissues, the functional importance of this hormone in calbindin synthesis and other normal mole-rat physiology is not known.
R Buffenstein, Department of Physiology, University of the Witwatersrand, Medical School, 7 York Road, Parktown 2193, South Africa