Objective To study the protective effect on transient focal cerebral ischemic preconditioning against neuronal cell apoptosis again,and the relationship between bcl 2, bax and cerebral ischemic tolerance.Methods Middle cerebral artery occlusion (MCAO) was showed for 20 min by craniotomy and MCA was blocked 6 h after 3 d.Cerebral infarct volume and the change of histopathological in rats were observed,the status of neuronal cell apoptosis were observed by TUNEL mothod,the alteration of bcl 2 and bax protein expression were observed by immunohistochemical method.Results As compared with the false preconditioning group and ischemia group,the infarct volume in the ischemic group reduced significantly after preconditioning( P

Objective To investigate the protective role of transient focal ischemic precondition(PC) against permanent focal cerebral ischemia, to define the proper time dose for precondition, and to study the reaction of astroglia in cerebral ischemic tolerance. Methods Temporary middle cerebral artery occlusion(10 minutes, 20 minutes, 30 minutes) followed three day reperfusion before permanent middle cerebral artery occlusion(PMCAO) transcranially was used as precondition in Wistar rats. The protective role was evaluated by observing the neurological deficits, analyzing the infarct volume and studying changes of pathohistology. The reaction of astroglia was observed by using anti GFAP immunohistochemistry.Results Compared with the control group, 20 min ischemic precondition, which did not produce neuronal damage obviously, alleviated the neurological deficits and reduced the infarct volume significantly( P