Two forms of gonadotropin-releasing hormone (GnRH), GnRH-I and GnRH-II, are commonly present in mammals. The main hormone controlling reproduction is GnRH-I acting through its receptor (GnRHR-I), whereas the function of GnRH-II is unknown. In primates, it has been suggested that GnRH-II is a specific agonist for the structurally distinct GnRHR-II. Here we compared effects of GnRH-I and GnRH-II on intracellular calcium and gonadotropin hormone release in neonatal rat gonadotrophs in vitro and the dependence of agonist actions on cyclic nucleotide levels. Both agonists elevated intracellular calcium and stimulated gonadotropin secretion in a concentration-dependent manner, with comparable peak amplitudes, but GnRH-I was three times more potent than GnRH-II. Antide, a specific GnRHR-I antagonist, completely blocked the action of both agonists on gonadotropin release. Inhibition of adenylyl cyclase activity by melatonin and MDL significantly attenuated GnRH-I- and GnRH-II-induced calcium signaling and gonadotropin release, whereas inhibition of soluble guanylyl cyclase activity was ineffective. GnRH-II also generated calcium oscillations in a fraction of gonadotrophs not expressing melatonin receptors. These results indicate that GnRH-I and GnRH-II act on the same GnRHR to stimulate gonadotropin release through intracellular calcium and cyclic nucleotide signaling, and that GnRH-II is less potent agonist for this receptor in neonatal rat gonadotrophs., A. Balík ... [et al.]., and Obsahuje seznam literatury
The role of gossypol in the cumulus expansion of oocyte-cumulus complexes (OCC) isolated from large antral porcine follicles was investigated. Marked suppression of cumulus expansion stimulated with follicle-stimulating hormone (FSH) and epidermal growth factor (EGF) was observed in the presence of different concentrations of gossypol. Comparable inhibitory effects were obtained in the presence of NO donor, S-nitroso-N-acetylpenicillamine or sodium nitroprusside, suggesting that the inhibitory effect of gossypol may be mediated via NO generation. The inhibitory effect of gossypol on cumulus expansion of OCC was accompanied by inhibition of progesterone secretion of OCC and the decrease of [125I]EGF binding to granulosa cells., J. Kolena, S. Vršanská, E. Nagyová, M. Ježová., and Obsahuje bibliografii
The effects of combined administration of two drugs elevating extracellular adenosine, namely dipyridamole (DP) and adenosine monophosphate (AMP), and granulocyte colony-stimulating factor (G-CSF) on hemopoietic stem cells in vivo were investigated. The experiments were performed on mice using the endogenous spleen colony formation in gamma-irradiated animals as an endpoint. The results have shown that DP and AMP act additively with G-CSF to enhance spleen colony formation and thus the erythroid repopulation of the spleen. These findings indicate that the signaling pathways of G-CSF and drugs elevating extracellular adenosine can interact at the level of primitive hemopoietic stem cells. The enhancement of hemopoiesis-stimulating effects of G-CSF by DP and AMP, which are low-priced and clinically available drugs, could improve the cost-effectiveness of the therapy with G-CSF., M. Hofer, M. Pospíšil, J. Netíková, V. Znojil, J. Vácha., and Obsahuje bibliografii
The aims of our study were to evaluate plasma levels of gut hormones in children with Type 1 diabetes mellitus (T1DM) in comparison with healthy contro ls and to corr elate plasma concentrations of gut hormones with blood biochemistry, markers of metabolic control and with anthropometric parameters. We measured postprandial levels of specific gut peptide hormones in T1DM children. Amylin, glucos e-dependent insulinotropic polypeptide (GIP), glucagon-like peptide 1 (GLP-1), ghrelin, leptin, pancreatic polypeptide (PP), and polypeptide YY (PYY) were assessed in 19 T1DM children and 21 healthy reference controls. Multiplex assay kit (LINCOplex®) was used for determination of the defined plasma hormone levels. T1DM subjects had significantly reduce d amylin (p<0.001) and ghrelin (p<0.05) levels, whereas GIP (p<0.05) was elevated when compared with healthy controls. Pl asma levels of other measured hormones did not differ statistically between the studied groups. Further analysis of T1DM patien ts demonstrated an association between body mass index and GL P-1 (r=0.4642; p<0.05), leptin (r=0.5151; p<0.05), and amylin (r=0.5193; p<0.05). Ghrelin levels positively correlated with serum HDL cholesterol (r=0.4760; p<0.05). An inverse co rrelation was demonstrated with triglycerides (TG) (r=-0. 5674; p<0.01), insulin dosage (r= -0.5366; p<0.05), and HbA1c% (r= -0.6864; p<0.01). Leptin was inversely correlated with TG (r= -0.6351; p<0.01). Stepwise regression analysis was performed to enlighten the predictive variables. Our study demonstrated an altered secretion pattern of gut peptide hormones in T1DM children. A close correlation was revealed between these peptides as well as with blood biochemistry, markers of me tabolic control and with anthropometric parameters. Further studies are essential to explore this issue in T1DM children., M. Huml ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Although in vitro studies have shown that cortisol concentrations in human and animal hair respond to environmental stressors, few data have been reported regarding the in vivo variability of hair cortisol to brief pain stressors. As an extension of a previous study, hair was collected and assayed for cortisol concentrations from each of three sites (elbow, mid-forearm, wrist) before and after participants immersed their hand in ice water for 1 min. Results showed that the "localization" boundary of hair cortisol responses previously reported was able to be reduced to only 250 mm between sites. Furthermore, all participants showed considerable variability in hair cortisol across the three sites at each collection period, although consistency across participants in overall responsivity of hair cortisol to the pain stressor was observed., C. F. Sharpley, K. G. Kauter, J. R. McFarlane., and Obsahuje bibliografii
I. Band, Enthaltend: Die Abnormitäten des Zellgewebes, der serösen und Schleim-Häute im Allgemeinen, der äussern Haut, des fibrösen, des Knochen-, Muskel-, Gefäss- und Nerven-Systemes, and von Carl Rokitansky
Sešit sedmý, Hasičská zdravověda, and vydává Zemská ústřední hasičská jednota Království českého ; společnou prací: Jak. Al. Jindra, Josef Hubálek, Mat. Mayer, Ad. L. Seidl.