Effect of whole body moderate hypothermia on expression of bclª²2 and bax in hippocampal CA1 after global cerebral ischemia and reperfusion in rats

    WANG Jun1,2, XIONG Liª²Ze1, WANG Jingª²Wei2, CAI Liª²Ping2, CAO Yan2, DU Wenª²Tao2, CHANG Jiang2

    1Department of Anesthesiology, Xijing Hospital, Fourth Military Medical University, Xi¬ðan 710033, China, 2Department of Anesthesiology, Shaanxi Provincial Corps Hospital, Chinese People¬ðs Armed Police Forces, Xi¬ðan 710054, China

    ¡¾Abstract¡¿ AIM: To observe the effect and mechanism of whole body moderate hypothermia on the expression of related gene after global cerebral ischemia and reperfusion. METHODS: According to the modified procedure of pulsinellis 4ª²vessel occlusion, we observed the changes of expression of bclª²2 and bax in ischemia group and the influence of hypothermia on these changes using immunohistochemistry assay. RESULTS: The level of bclª²2 expression was low at 6 h postª²ischemia injury and it increased gradually with the passage of time. The expression reached peak level at 24 h and reduced at 7 d. Low expression was also observed in hypothermia group but it reached the peak at 3 d. Significant difference in the expression level of bclª²2 at 3 d was found between ischemia group and hypothermia group (P<0.01). The level of bax expression increased at 6 h after ischemia, reached the peak at 5 d and remained high at 7 d. Compared with that in ischemia group, the expression of bax were markedly lower at 5 d and 7 d (P<0.01) in hypothermia group and no peak was observed. CONCLUSION: Hypothermia can inhibit the expression of bax, the gene that promotes neuronal apoptosis. The inhibition of neuronal apoptosis may contribute to the preventive effect of hypothermia on global ischemia. ......