降钙素基因相关肽介导的离体大鼠心脏缺血预处置

Ischemic preconditioning mediated by calcitonin gene related peptide in isolated rat hearts 1

降钙素基因相关肽介导的离体大鼠心脏缺血预处置１肖洲生，李元建２，邓汉武（湖南医科大学药理教研室，长沙４１００７８，中国）关键词降钙素基因相关肽；心肌再灌注损伤；心功能试验；肌酸激酶目的：研究降钙素基因相关肽（ＣＧＲＰ）在离体大鼠心脏缺血预处置（ＰＣ）...

IM: To study the mediating effect of calcitonin gene related peptide (CGRP) in ischemic preconditioning in the isolated perfused rat heart. METHODS: Isolated rat hearts were subjected to 3 cycles of a 5 min ischemia and a 5 min reperfusion before a 30 min global ischemia followed by a 30 min reperfusion. RESULTS: Ischemic preconditioning caused an improvement of heart functions, reduced the incidence of ventricular arrhythmias and decreased the release of creatine kinase (CK) during reperfusion (CK activities=0 30±0 07, 2 03±0 49, and 0 92 ±0 40 U·min -1 /g wet wt for control, ischemia reperfusion, and preconditioning, res￣pec￣tively). However, pretreatment with CGRP 8-37 (0 1 μmol·L -1 ) abolished the improve￣ment of cardiac contractivity, the reduction of the incidence of arrhythmias, and the inhibition of CK release by preconditioning (CK activities=0 9±0 4 vs 2 55 ±0 32 U·min -1 /g wet wt , P <0 01) . CONCLU￣SION: CGRP is an endogenous myocardial protective substance that played an important role in mediation of ischemic preconditioning.