兔缺血预适应心肌中环氧化酶-2的表达及阿司匹林的影响作用

Expression of cyclooxygenase-2 in ischemic preconditioning myocardium and the effect of aspirin on prostaglandin metabolites in rabbit

目的 观察兔晚期缺血预适应 (DPC)心肌中环氧化酶 2(COX 2)的表达量以及不同剂量阿司匹林对其影响。方法 新西兰兔 32只,随机分为 4组,DPC组(A组,n=8);正常对照组 (B组,n=8 );小剂量阿司匹林 ( 10mg/kg) +DPC组(C组,n=8);大剂量阿司匹林 (20mg/kg) +DPC组(D组,n=8)。结扎兔冠状动脉左前降支建立缺血预适应模型, 24h后取心肌组织,使用Western blotting及免疫组化方法分别测定兔DPC心肌中COX 2的表达。结果 兔DPC心肌COX 2表达量比对照组明显上升,差异有显著性 (P<0 01);实验前分别给予小、大剂量阿司匹林对COX 2表达量影响较小,差异无显著性(P>0 05)。结论 兔DPC心肌中COX 2明显表达,缺血预适应分别前予小、大剂量阿司匹林对COX 2表达量影响较小。

Objective To observe the expression of cyclooygenase 2(COX 2) in delay ischemic preconditioning myocardium and the effect of Aspirin on prostaglandin metabolites in rabbits. Methods New Zealand rabbits( n =32)were randomly divided into 4 groups:group A( n =8):delay ischemic preconditioning, group B( n =8):normal controls,group C( n =8):low dosage aspirin(10 mg/kg)and delay ischemic preconditioning,group D( n =8):high dosage(20 mg/kg)aspirin and delay ischemic preconditioning. A mode of ischemic preconditioning myocardium was reproduced by ligation left anterior descending branch. After 24 hours, the COX 2 of myocardial section were investigated by Western blotting and immunohistochemistry. Results The expression of COX 2 in group A was significantly higher than in group B ( P <0 01).The levers of COX 2 were not higher in group C than that in group D and did not differ significantly from group B( P >0 05). Conclusion The COX 2 protein is expressed in delay ischemic preconditioning myocardium in rabbits.The COX 2 protein is not inhibited by high dosage aspirin on prostaglandin metabolites in rabbits as low dosage aspirin as well.