脑缺血再灌注损伤的海马神经元对Bax、Bcl-2和Caspase-3的表达

目的：凋亡调控基因在脑缺血再灌后海马神经元的表达。方法：采用免疫组织化学的方法，观察 昆明小鼠双侧颈总动脉结扎7min后不同再灌时间组(24h组、48h组、72h组、7d组、14d组)海马CAl区神经元Bax、Bcl-2和Caspase-3的活性形式CM1的免疫反应活性。结果：Bax和CM1阳性神经元数在48h组最多，与其他各组相比差异有显著性(P＜0．01)，72h组明显下降，14d组完全消失；而Bcl-2阳性神经元数在48h组增多(与24h组相比，P＜0．01)，72h组下降，7d组再次上升(与72h组相比，P＜0．01)，14d组最多(与48h组相比，P＜0．01)。在24h、48h、72h、7d组，Bax阳性神经元多于Bcl-2阳性神经元(P＜0．05)，14d组则相反。结论：Bax和caspase-3在脑缺血再灌早期表达增强，然后下降以至消失，Bcl-2于再灌后期表达增强。Bax表达上调可能与Caspase-3激活相关。

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,P<0.01) .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 (P<0.05). 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.