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Research on cell injury due to Carbon Monoxide and Nitric Oxide under ischemia or shock

缺血或休克时一氧化碳和一氧化氮所致细胞损伤的研究

基本信息

批准号：
14370152
负责人：
YOSHIDA Ken-ichi
金额：
$ 9.73万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2003
项目状态：
已结题

项目摘要

Heme-oxygenase (HO)-1, generates CO, thereby protecting the cells. We have shown that a Ca^<2+>-dependent protease calpain promotes necrotic death in the cardiogenic H9c2 cells under hypoxia through α-fodrin proteolysis. The Ca^<2+>-influx, α-fodrin proteolysis and schemic death, were inhibited by CO or L-type Ca^<2+>-channel inhibitor verapamil. Ischemia also induced mitochondrial depolarization, which was inhibited by CO or verapamil. HO-1 induction reduced the Ca^<2+>-influx and cell death after ischemia. Thus, exogenous and endogenous CO protect the cardiomyogenic cells against ischemia by inhibiting Ca^<2+>-influx through L-type Ca^<2+> channel and calpain activation.After short (15, 30 min) and long (45, 60 min) time. of ischemia by coronary artery occlusion of the rats, reperfusion caused dilatation and constriction of arterioles, respectively. The vascular diameter was correlated with enhanced immunofluorescence for Akt and phosphorylated forms of serine 1177 residue 鋲NOS, and NO-bound form of guanylate cyclase (GC), as confirmed by western blotting. The constriction during reperfusion after 45 min of ischemia is related to the inhibition of Akt-mediated eNOS-Ser1177 phosphorylation, which was suppressed by a PKC inhibitor chelerythrine, a flavoprotein inhibitor DPI, or reactive oxygen species (ROS) scavengers MPG and Tiron. An endothelin receptor antagonist BQ123 alleviated the vasoconstriction by increasing NO availability but not eNOS phosphorylation. Thus, vascular patency correlated with eNOS-Ser1177 phosphorylation during ischemia-ieperfusion, and is affecled by ROS, PKC, and flavoproteins.

血红素加氧酶(HO)-1产生一氧化碳，从而保护细胞。我们已经证明，一种钙依赖的蛋白水解酶Calain通过α-fodrin蛋白分解促进缺氧条件下心源性H9c2细胞的坏死性死亡。CO或L型钙通道阻断剂维拉帕米可抑制钙离子内流、α-fodrin蛋白降解和缺血死亡。缺血还可引起线粒体去极化，这种作用可被CO或维拉帕米抑制。HO-1的诱导减少了缺血后钙离子内流和细胞死亡。因此，外源性和内源性CO通过抑制L型钙通道内钙内流和钙激活来保护心肌细胞免受缺血的损伤，作用时间短(15，30分钟)和长(45，60分钟)。冠脉结扎致大鼠缺血时，再灌流分别引起小动脉扩张和收缩。血管直径与Akt、磷酸化丝氨酸1177残基鋲和NO结合型鸟苷环化酶(GC)的免疫荧光增强相关，经Western blotting证实。缺血45min再灌流时的收缩与Akt介导的eNOS-Ser1177磷酸化受到抑制有关，PKC抑制剂白屈菜红碱、黄素蛋白抑制剂DPI或ROS清除剂MPG和TIron均可抑制该作用。内皮素受体拮抗剂BQ123通过增加NO的供应而减轻血管收缩，但不增加eNOS的磷酸化。因此，血管通畅性与eNOS-Ser1177在缺血再灌流过程中的磷酸化有关，并受ROS、PKC和黄素蛋白的影响。