磺脲类药物受体亚型在缺血及缺血预适应大鼠心肌中的定位与分布研究

Studies on expression and regional distribution of sulfonylurea receptor in the reperfusion and ischemic preconditioning rat heart

目的 探讨缺血再灌注及缺血预适应 (IPC)状态心肌磺脲类药物受体 (SUR)亚型SUR2的分布及表达特征。方法 建立大鼠心肌在体IPC模型及缺血再灌注模型 ,采用体外受体放射自显影技术检测正常对照、缺血再灌注及IPC时大鼠心肌中SUR2的定位与分布模式 ,并用图像分析仪对其表达密度作半定量分析。结果 ①与对照区相比 ,缺血再灌注缺血区相对透光度增高 ,其平均增高幅度为 (4 1.0± 9.3) % ;②IPC区与对照区相比相对透光度也增高 ,其平均增高幅度为 (17 1±2 3) % ;③IPC组相对透光度增高幅度小于缺血再灌注组 (χ2 =5 .2 73,P <0 .0 5 )。结论 缺血再灌注及IPC时SUR2表达密度均降低 。

Objective To investigate the characteristics of expression and regional distribution of sulfonylurea receptor subtype 2 (SUR2) in the reperfusion and ischemic preconditioning (IPC) rat heart. Methods In vivo rat models of IPC and in vivo rat moldels of reperfusion were made. With 3H glibenclamide as radioligand, using in vitro receptor autoradiography, patterns of SUR2 expression and regional distribution were studied in tissue sections of reperfusion and IPC rat heart. Additionally, the expression density was analyzed semi quantitatively by using an image analyzing system. Results The OD values of reperfusion group were higher than the values of normal group and the average increasing range was (41.0±9.3)%; the OD values of IPC group were also higher than the values of normal group and the average increasing range was (17.1±2.3)%; the increasing range of IPC group was significantly smaller than that of reperfusion group ( χ 2=5.273, P <0.05). Conclusion Comparing to the normal group, the expression of SUR2 in the rat heart of reperfusion group and IPC group reduced, but, at the same time, the reducing range of expression of SUR2 in IPC group was smaller than the range in reperfusion group.