目的　探讨自噬标志分子LC3B在大鼠全脑缺血复灌不同时间的表达以及对海马神经元损伤的影响。  方法　采用四血管法(4-vessel-occlusion，4-VO)法制作大鼠全脑缺血模型，随机将33只　SD大鼠分成假手术组和缺血再灌注组。在大鼠全脑缺血20 min后，分别恢复血流灌注30 min、1、2、4、6、8、12、24、48、72 h，用免疫组织化学法检测海马CA1区神经元LC3B的表达。  结果　LC3B在大鼠全脑缺血20 min复灌2 h开始表达，在复灌12 h表达到达高峰，之后逐渐减弱。  结论　自噬的激活介导了大鼠全脑缺血再灌注海马CA1区神经元的损伤死亡，长时间脑缺血再灌注损伤中自噬激活的时间更早及介导神经元的损伤更严重。

Objective　To explore expression change of LC3B in hippocampus, and the hippocampal neuronal death after global cerebral ischemia/reperfusion in rats.　Methods　Transient global cerebral ischemia was induced by four-vessel occlusion method. The SD rats weighing 250~320 g were randomly divided into 2 groups: the sham-operated group and the ischemia/reperfusion group. The expression of LC3B was detected by immunohistochemistry analysis.　Results　The expression of LC3B in the ischemia/reperfusion group got increased after 2h of reperfusion, and the peak appeared at 12 h of reperfusion.　Conclusions　The occurred LC3B activation leads to the neuronal death of hippocampal CA1 induced by ischemia/reperfusion. The earlier high expression of LC3B occurred, the more severe neuronal death appeared after 20-min global cerebral ischemia. These results suggest that autophagy pathway play a more harmful role in neuron death after long time ischemia.