Liu Yanping, Li Hongwei, Bubolz Aaron H, Zhang David X, Gutterman David D
The National Center for Research Resources, National Institutes of Health, Bethesda, MD, USA.
Med Biol Eng Comput. 2008 May;46(5):469-78. doi: 10.1007/s11517-008-0331-1.
Mitochondrial H2O2 contributes to flow-mediated dilation (FMD) in human coronary arterioles (HCA). We examined the hypothesis that the endothelial cytoskeleton plays a critical role in transducing endothelial wall shear stress into a stimulus for releasing mitochondrial ROS. Phallacidin together with alpha-, beta-tubulin antibodies and Mito-Tracker Red showed the proximity of F-actin, microtubules and mitochondria in endothelial cells. Cytochalasin D (CytoD) and nocodazole (Noc) disrupted endothelial F-actin and microtubules in HCA, respectively, concurrent with a reduction in the generation of cytosolic and H2O2 (hydroethidine and dichlorodihydrofluorescein fluorescence) and mitochondrial superoxide (mitoSox) during flow (control: 3.5 +/- 1.6, Cyto D: 0.51 +/- 0.2, Noc: 0.81 +/- 0.6). FMD, but not the dilation to bradykinin or papaverine, was reduced by Cyto D (26 +/- 10% vs. 56 +/- 3%) or Noc (26 +/- 11% vs. 58 +/- 7%). These results suggest that cytoskeletal elements are a critical component of the signaling mechanism linking endothelial shear stress and mitochondrial release of ROS in the human coronary microcirculation.
线粒体过氧化氢参与人体冠状动脉小动脉（HCA）的血流介导的血管舒张（FMD）。我们检验了如下假设：内皮细胞骨架在将内皮壁切应力转化为释放线粒体活性氧的刺激信号过程中起关键作用。鬼笔环肽与α-、β-微管蛋白抗体以及线粒体追踪染料共同显示了内皮细胞中F-肌动蛋白、微管和线粒体的接近程度。细胞松弛素D（CytoD）和诺考达唑（Noc）分别破坏了HCA中的内皮F-肌动蛋白和微管，同时在血流过程中细胞溶质和过氧化氢（氢化乙锭和二氯二氢荧光素荧光）以及线粒体超氧化物（MitoSox）的生成减少（对照：3.5±1.6，Cyto D：0.51±0.2，Noc：0.81±0.6）。Cyto D（26±10%对56±3%）或Noc（26±11%对58±7%）降低了FMD，但对缓激肽或罂粟碱诱导的血管舒张没有影响。这些结果表明，细胞骨架成分是连接人体冠状动脉微循环中内皮切应力和线粒体活性氧释放的信号传导机制的关键组成部分。
