Abstract:Objective:To study the relationship of the level of phospho-p38MAPK (p-p38MAPK) and the number of survival neurons in hippocampal CA1 regions by ischemic preconditioning(IP) after cerebral ischemic-reperfusion(IR). Methods:The model of ischemic-preconditioning in gerbil was established. The animals were randomly allocated into SH group,ischemia in advance group(IA group),IR group and IP group. After the last ischemia,the animals of the last three groups were respectively further allocated into subgroups of 15 min,2 h,6 h,1 d and 5 d after reperfusion with 8 animals in each subgroup. The p-p38MAPK in hippocampal CA1 regions was detected by immunohistochemistry and semiquantitive analyzed using Leica Qwin image analysis system in the former 4 subgroups. The behavioral and morphologic changes were detected in last 2 subgroups. The myringa temperature of gerbils sustained at (37±0.5) ℃ from the beginning of ischemia to recovery from anesthesia. Results:There was few p-p38MAPK detected in hippocampal CA1 regions in SH group. The level of p-p38MAPK in hippocampal CA1 region in IA group was significently higher than that of SH group,but significently lower than that of IR group at 15 min,2 h,6 h and 1 d respectively. The level of p-p38MAPK in hippocampal CA1 region in IP group was significently higher than that of IA group at 15 min and 2 h respectively,but was remarkably lower than that of IR group at 15 min,2 h,6 h and 1 d respectively. The behavioral examination showed that gerbils scrawed more actively in IR group at 1 d and 5 d and in IP group at 1 d than those of SH group. Gerbils in IP group scrawed much less actively at 1 d and 5 d than those of IR group. The survival neurons in hippocampal CA1 region of IR group and IP group were less than those of SH group at 1 d and 5 d respectively. The survival neurons of hippocampal CA1 region in IP group were significently more than those of IR group at 1 d and 5 d respectively,but less than those of IA group at 5 d after reperfusion. Conclusions:The level of p-p38AMPK in hippocampal CA1 increased after 3 min IR,and it could reduced the level of p-p38MAPK after another longer time IR after 1 d. IP reduced hippocampal CA1 neurons death and attenuated behaveral changement after longer time IR.