Changes of endothelial function indices and their relation to platelet activation in idiopathic atrial fibrillation / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the changes of endothelial function indices and their relation to platelet activation in patients with idiopathic atrial fibrillation (AF).</p><p><b>METHODS</b>We studied 61 patients with idiopathic AF with 34 age- and sex-matched healthy persons as control. Platelet counts in the blood were tested, and plasma levels of NOx were analyzed using Griess method. The plasma levels of von Willibrand factor (vWF) and soluble P-selectin (sP-selectin) were determined using enzyme-linked immunosorbent assay.</p><p><b>RESULTS</b>Compared to healthy control, the patients with idiopathic AF had significantly lower levels of plasma NOx (18.2-/+7.3 vs 24.3-/+7.8 micromol/L, P=0.049) and higher levels of plasma sP-selectin (25.6-/+6.2 vs 22.4-/+4.8 ng/ml, P=0.007). No significant differences were found in the platelet counts or plasma vWF levels between the two groups. A significant inverse correlation was found between plasma NOx and sP-selectin (r=-0.405, P=0.025) in patients with idiopathic AF.</p><p><b>CONCLUSION</b>AF per se may impair the endothelial function and activate platelet function, suggesting the role of endothelial dysfunction in activated platelet function in AF patients.</p>

Effects of oxygen and calcium on the expression of wild-type and mutated hypoxia-inducible factor-1alpha eukaryotic vectors in HEK293 cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the effects of oxygen and calcium on the expression of eukaryotic vectors harboring wild-type or mutated hypoxia-inducible factor-1alpha (HIF-11alpha) in HEK293 cells.</p><p><b>METHODS</b>HEK293 cells were transiently transfected with pcDNA3.1+/HIF-11alpha, pcDNA3.1+/HIF-11alpha-564Ala and pcDNA3.1+/HIF-11alpha-564Ala-803Ala via lipofectin. Western blotting were used to detect HIF-11alpha protein after normoxic or hypoxic exposure of the transfected HEK293 cells in the presence or absence of Ca(2+). The levels of vascular endothelial growth factor (VEGF) mRNA in the transfected cells in normoxic condition was detected using RT-PCR.</p><p><b>RESULTS</b>The levels of HIF-11alpha protein and VEGF mRNA increased in HEK293 cells transfected with the vectors harboring mutated HIF-11alpha, but not in the cells transfected with wild-type HIF-11alpha vectors in normoxia. Hypoxia increased the levels of HIF-11alpha protein in the cells transfected with wild-type HIF-11alpha vectors, which was inhibited by the application of Ca(2+). Ca(2+) showed no inhibitory effect on HIF-11alpha levels in HEK293 cells transfected with the vectors containing mutated HIF-11alpha.</p><p><b>CONCLUSION</b>The protein products of pcDNA3.1+/HIF-11alpha-564Ala and pcDNA3.1+/HIF-11alpha- 564Ala-803Ala in HEK293 cells enhance the cell tolerance to oxygen and protease.</p>

Effect of porcine relaxin on NO production of human microvascular endothelial cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe effect of porcine relaxin(pRLX) on NO production of human microvascular endothelial cells(HMVECs) and discuss its possible mechanism.</p><p><b>METHODS</b>iNOS and cNOS expression of HMVECs with or without pRLX were detected using western blotting. NO production of HMVECs with pRLX at different concentration or different time were determined by method of Griess. NO production of pRLX of HMVECs plus Non-selective NOS inhibitor NG-monomethyl-L-arginine(L-NMMA), selective iNOS inhibitor aminoguanidine(AG) or nuclear factors-kappaB (NF-kappaB) inhibitor pyrrolidine dithiocarbamate(PDTC) were also analysed.</p><p><b>RESULTS</b>pRLX promoted iNOS protein expression of HMVECs, but not cNOS protein expression. NO production of HMVECs was promoted by pRLX on concentration-dependent pattern instead of time-dependent one. AG, L-NMMA and PDTC were showed to block the effect of pRLX on NO production of HMVECs.</p><p><b>CONCLUSION</b>pRLX promote iNOS expression and NO production of HMVECs.</p>