清醒家兔缺血再灌注心肌内皮素释放特征及意义

Characteristics and significance of endothelin release in ischemiareperfused myocardium in conscious rabbits

43只对照兔和12只高脂喂养的实验兔,在清醒状态下遭受心肌缺血0.5h后获得再灌注。放免法测定内皮素(ET)含量。对照兔心肌组织ET含量在缺血未坏死区于缺血0.5h高于缺血0h,于再灌注6h、24h。48h和72h均高于缺血0.5h。在坏死区于再灌注6h高于缺血0.5h,于再灌注14h低于缺血0.5h,在未缺血区于再灌注6h、24h和48h均高于缺血0.5h。实验兔非缺血区和缺血末坏死区心肌组织ET含量于再灌注6h和48h均显著高于对照兔。提示,心肌组织ET释放的时间及区域特征与组织受损程度密切相关,在冠状动脉粥样硬化基础上并发急性缺血再灌注过程,ET释放进一步增强。

The present study used 43 control rabbits and 12 experimental rabbits fed with rich cholesterol and pork fat. They were subjected to 0.5 h of left ventricular branch occlusion followed by reperfusion in conscious status. Endothelin(ET) content in myocardial tissue was determined by radioimmunoassy. In ischemic non-necrotic area ET contents increased significantly at 0.5 h of occlusion, and increased further at 6 h, 24 h. 48 h and 72 h of reperfusion. In necrotic area ET contents was higher at 6 h and lower at 24 h of reperfusion than at 0.5h of ischemia. In non-ischemic area ET contents was also increased mildly at 6 h. 24 h and 48 h of reperfusion than at 0.5 h of ischemia. In non-ischemic area and ischemic non-necrotic area ET contents were very much higher at 6 h and 48 h in experimental rabbits than that of the control rabbits. The results suggested that the lime and regional characteristics of ET release in myocardial tissue are closely related to the extent of myocardial injury, and when the event of myocardial ischemia and reperfusion occurs on the basis of coronary atherosclerosis. ET release has a further increase.