ABSTRACT
Objective To investigate the relation between the expression of Bcl-2 protein and protection against ischemic neuronal damage by preconditioning with sublethal ischemia .Methods The cerebral ischemia was induced by occlusion of bilateral common carotid arteries .Sixty-three gerbils were divided randomly into four groups:sham operative control group (group A,n=5),ischemic preconditioning control group (group B ;n=6) with a single 2-min cerebral ischemia; ischemia preconditioning group (group PC,n=26) and ischemic control group (group IR,n=26) with 5-min ischemia being induced following 3 days of reperfusion with or without 2-min ischemic preconditioning,then with reperfusion lasting 4 hours (group PC1,n=5;group IR1,n=5),24 hours (group PC2,n=7;group IR2,n=7),72 hours (group PC3,n=7;group IR3,n=7)or 7 days (group PC4,n=7;group IR4 ,n=7) respectively.Paraffin sections of hippocampus were used for Bcl-2 protein immunohistochemical staining.Results In group B,Bcl-2 protein immunoreactivity (the intensity of staining) significantly increased as compared with that in group A(P