Medicine and Health Sciences Commons^™

H2o2‐Induced Microvessel Barrier Dysfunction: The Interplay Between Reactive Oxygen Species, Nitric Oxide, And Peroxynitrite, Xueping Zhou, Yan Qian, Dong Yuan, Qilong Feng, Pingnian He

Faculty & Staff Scholarship

Elevated H2O2 is implicated in many cardiovascular diseases. We previously demonstrated that H2O2-induced endothelial nitric oxide synthase (eNOS) activation and excessive NO production contribute to vascular cell injury and increases in microvessel permeability. However, the mechanisms of excessive NO-mediated vascular injury and hyperpermeability remain unknown. This study aims to examine the functional role of NO-derived peroxynitrite (ONOO) in H2O2-induced vascular barrier dysfunction by elucidating the interrelationships between H2O2-induced NO, superoxide, ONOO, and changes in endothelial [Ca2+ ]i and microvessel permeability. Experiments were conducted on intact rat mesenteric venules. Microvessel permeability was determined by measuring hydraulic conductivity (Lp). Endothelial [Ca2+ ]i, …