降钙素基因相关肽对大鼠心肌缺血损伤的影响

目的:观察降钙素基因相关肽对大鼠缺血心肌的保护作用。方法:用单剂量异丙肾上腺素皮下注射复制大鼠心肌缺血损伤模型,单剂量降钙素基因相关肽静脉注射治疗,2 h后采血测定血清心肌酶及血清MDA、SOD水平,同时取心肌组织匀浆测组织MDA、SOD水平,并观察心肌组织结构改变。结果:(1)异丙肾上腺素致缺血心肌损伤大鼠血清和心肌组织MDA升高、SOD下降,而CGRP治疗能逆转上述改变(P＜0.05)。(2)CGRP治疗组心肌酶CK、LDH明显低于损伤组(P＜0.05)。(3)心肌光镜、电镜结果示CGRP组细胞损伤程度明显低于损伤组(P＜0.05)。结论:CGRP对异丙肾上腺素所致大鼠缺血心肌有保护作用,抗膜脂质过氧化可能是其重要机制。

Effect of calcitonin gene-related peptide (CGRP) on myocardial ischemic injury in rat

AIM: To study the protective effects of intravenous (iv) CGRP on myocardial injury in rat. METHODS: Establish a rat myocardial ischemic injury model by subcutaneous injection of single dose of isoproterenol (ISO), and treat the model with single dose of iv CGRP. Two hours later, serum CK, LDH, MDA and SOD levels were measured, MDA and SOD in myocardial tissue were tested, and myocardial tissue structures were observed. RESULTS:(1) Serum MDA and tissue MDA levels increased significantly and serum SOD and tissue SOD decreased significantly in injury group, in the CGRP treated group, the above changes were reversed (P<0.05). (2) Serum CK and LDH levels of the treated group decreased significantly when comared with injury group(P<0.05). (3) Microscopic and electron microscope observation showed that degree of injury of myocardial structure in the CGRP treated group was slighter than injury group (P<0.05). CONCLUSION: Iv CGRP had protective effect on ischemic myocardium produced by isoproterenol, inhibition of membrane lipid peroxidation maybe its important machanism.