Objective: To investigate the expression of Bak and Bad gene after ischemia-reperfusion. Methods: Ischemia was induced by the four-vessel occlusion for 30 min and followed by reperfusion in rats. The biopsy tissue from brain was immunohistochemically assayed with Bak and Bad genes polyclonal antibody . Results: The expression of Bak protein decreased as early as 12h after onset of reperfusion and peaked at 24~48h. At the same time
however
the expression of Bad protein increased and peaked at 24~48h. The expression of Bak and Bad gene was quite clear in cortex and hippocampus CA1 which were the sensitive areas for ischemic injury. Conclusion: The ischemia-reperfusion induced the changes of expression of Bak and Bad gene in brain which may accelerate apoptosis of neurons.