摘要
目的应用一氧化氮合酶(nitric oxide synthase,NOS)抑制剂及神经节阻滞剂,探讨非创伤性肢体缺血预处理对缺血/再灌注心肌保护作用的可能机制。方法Wistar大鼠64只,制备大鼠心肌缺血/再灌注的动物模型,随机分为4组,缺血/再灌注组(Ⅰ组),非创伤性肢体缺血预处理组(PL组),L-NAME+非创伤性肢体缺血预处理组(PL-N组),神经节阻滞剂六甲双胺+非创伤性肢体缺血预处理组(PL-H组)。实验结束,用TTC染色的方法测定大鼠心梗面积。每组另取8只大鼠,待实验结束后取缺血区心肌组织,测定NO、NOS及iNOS,应用反转录PCR技术,测定iNOS mRNA。结果PL组和PL-H组心肌梗死面积较Ⅰ组明显缩小(P<0.05),而PL-N组与Ⅰ组相比差异无显著性。PL组和PL-H组心肌组织NO含量较Ⅰ组明显升高,NOS、iNOS活性亦升高(P<0.05);PL-N组NO含量较I组略降低,但差异无统计学意义。PL组和PL-H组较I组心肌组织iNOS mRNA明显升高(P<0.05);而PL-N组iNOS mRNA表达较Ⅰ组无变化。结论内源性一氧化氮在肢体缺血预处理的早期心脏保护中起重要作用,而神经元途径在肢体缺血预处理的心肌保护中无明显作用。
Aim To investigate a possible role for nitric oxide and neurogenic pathway in the protective effect of the limb preconditioning on the ischemic-reperfusion myocardium.Methods 64 Wistar rats were randomly divided into one of the four experimental groups.In Group Ⅰ,the rats underwent 30 min occlusion of the left anterior descending coronary artery,and 120 min reperfusion.In Group PL,the rats underwent four cycles of 5 min occlusion and reperfusion of both hind limbs using a tourniquet before the experiment was continued as in Group Ⅰ.In Group PL-N and Group PL-H,rats were administered with L-Nitro-Arginine Methyl Ester（L-NAME）10 mg·kg^-1 or hexamethonium chloride 20 mg·kg^-1,intravenously,20 min before IPC.Infarct size,as a percentage of the area at risk,was determined by triphenyltetrazolium chloride staining.And other 8 rats in each group,at the end of the experiment,all rats were killed and myocardium were stored in liquid nitrogen for the measurement of NO,NOS,iNOS and iNOS mRNA.Results The myocardial infarct size（IS）was decreased significantly in Group PL and Group PL-H compared with Group Ⅰ（P〈0.05）.There was no significant difference between Group PL-N and Group Ⅰ（P〈0.05）.The levels of NO,NOS,iNOS,iNOS mRNA were increased in Group PL and PL-H compared with Group Ⅰ（P〈0.05）,and no significant changes in Group PL-N.Conclusions Noninvasive limb IPC is effective in protecting the myocardium from ischemia reperfusion injury.NO plays an important role in the mechanism of this acute remote preconditioning.
出处
《中国药理学通报》
CAS
CSCD
北大核心
2007年第11期1490-1493,共4页
Chinese Pharmacological Bulletin
基金
辽宁省自然科学基金资助项目(No20052115)
