Expression of Bax, Bcl-2 and Caspase-3 in hippocampal CA1 region following cerebral ischemia-reperfusion injury

Objective:To explore the expression of apoptosis regulated genes of hippocampus after cerebral ischemia-reper-fusion. Methods: With immunohistochemical method, the immunoreponsive activity of Bax,Bcl-2 and CM1 (active form of Caspase-3) were observed in hippocampal CA1 region of Kunming mice following transient bilateral common carotid arteries (BCCA) ligation with 7 min and different reperfusion period (24 h,48 h,72 h,7 d, 14 d group). Results:The number of Bax and CM1 positive neurons was more in 48 h than all other ones (P 0.01). Their expession decreased significantly in 72 h group,and could not be detected in 14 d group. The number of Bcl-2 positive neurons was increased in 48 h group (compared with the 24 h group,P0.01) .which was decreased in 72 h group. However.it increased again in 7 d group, and reached the peak on 14 d. The number of Bax positive neurons was significantly more than the number of Bcl-2 positive neurons in 24 h,48 h,72 h,7 d,14 d group (P0.05). On contrast,it was reverse in 14 d group. Conclusion:The expression of Bax and Caspase-3 is increased in early reperfusion period,so does the expression of Bcl-2 in late reperfusion period; and the expression of Bax exceeding Bcl-2 may be associated with the activation of Caspase-3.