二氮嗪介导的延迟预处理对未成熟心肌的保护机制研究  

The Myocardioprotection of Delayed Preconditioning Elicited by Diazoxide on Prematured Myocardium

作　　者：王欣[1] 张翔[1] 张晓玲[1] 

机构地区：[1]中国医学科学院阜外心血管病医院心外科,北京100037

出　　处：《实用临床医药杂志》2008年第2期6-9,共4页Journal of Clinical Medicine in Practice

基　　金：国家自然科学基金资助项目(30500534)

摘　　要：目的研究二氮嗪(DZX)介导的延迟预处理对缺血缺氧环境中未成熟心肌的保护作用机制。方法分离培养新生鼠心肌细胞随机分为:①缺氧组;②DZX组:细胞缺氧培养前24 h放入含100μmol/L的DZX的培养液15 min;③DZX+PDTC组:细胞缺氧培养前24 h放入含100μmol/L DZX和500μmol/L二硫代氨基甲酸吡咯烷(PDTC)的培养液15 min;④对照组。前3组细胞在缺氧模型中培养16 h,对照组一直有氧培养。采用Hoechst染色、Annexin V/PI流式检测凋亡细胞,Western Blot检测心肌细胞Bax和Bcl-2的表达。结果①流式检测示DZX组较缺氧组细胞凋亡明显降低(P<0.01),Hoechst染色心肌凋亡细胞也减少;②与DZX组比较,加入PDTC后,流式检测显示细胞凋亡显著增多(P<0.01),Hoechst染色心肌细胞凋亡增多,Western blot检测显示Bcl-2表达减少,Bax表达增加。结论线粒体钾通道开放剂二氮嗪介导的延迟预处理对心肌有明显的保护作用;位于下游的NF-κB通过调控促凋亡蛋白Bax和抗凋亡蛋白Bcl-2的的表达在未成熟心肌的延迟预处理中起着关键作用。Objective To study the protective effect of delayed IPC mediated by mito KATP opener Diazoxide on Pre-matured myocardlum. Methods The myocardial cells of newborn rats were randomly divided into anoxic, DZX, DZX ＋ PDTC and control group. The DZX group was placed in culture fluid of 100μmol/L DZX for 15 minutes before cellular anoxic cultivation; the DZX ＋ PDTC one in culture fluid of 100μmol/L DZX and 500μmol/L PDTC for 15 minutes before cellular anoxic cultivation; and the control and anoxic groups in blank solvent for 15 minutes. Then the myocardial cells of anoxic, DZX and DZX ＋ PDTC group were cultivated in anoxic condition for 16 hours, and those of the control group were constantly cultivated with oxygen. Various indexes were detected, including Flow Cytometry Using Annexin V and Propidium Iodide Double Staining; Bax and Bcl-2 by Western Blot; Hoechst dyeing. Results Compared with the anoxic group, the DZX one could obviously inhibit the myocardial apoptosis of neonate rats induced by Hypoxia/SD, by flow cytometry and by Hoechst dying. Compared with DZX group, the myocardial apoptosis of DZX ＋ PDTC group was obviously increased, by flow cytometry and by Hoechst dyeing. And, the expressions of protein bcl-2 and bax of DZX ＋ PDTC group were increased, but the expressions of protein bax of one were decreased, as determined by western blot. Conclusion Delayed IPC mediated by mito KATP opener DZX, had obvious protective effect on cardiac muscle. While the activation of transcription faetorNF-κB at the lower reach of mito KATP played an essential role in the delayed IPC of pre-matured cardiac muscle

关 键 词：未成熟心肌细胞 缺血预处理 二氮嗪 NF-ΚB 

分 类 号：R542.2[医药卫生—心血管疾病]