类缺血再灌注小鼠皮质神经元DNA单链损伤与Bax表达的关系

Relationship between DNA single strand damage and Bax expression in mouse cerebral cortical neurons under ischemic like conditions

目的 :研究神经元类缺血再灌注不同时间点DNA单链损伤和Bax的表达情况 ,探讨神经元类缺血再灌注时DNA单链损伤与Bax表达的关系 .方法 :利用流式细胞仪对小鼠皮质神经元类缺血再灌注损伤后Bax的表达进行检测 .应用Klenow法对缺血再灌注各时间点培养的神经元DNA单链损伤进行检测和半定量分析 .结果 :类缺血处理后再灌注不同时间点Bax的表达不同 ,再灌注 2h最强 ,而后随着再灌注时间的延长Bax的表达下降 .Klenow法检测发现未经缺血处理的对照组神经元平均灰度为 72 .4± 1.0 ,到达 2h达高峰13 5 .5± 1.3 ,而后又逐渐降低 .再灌注不同时间点Bax表达的阳性率与Klenow法检测的平均灰度成线性相关 .结论 :神经元类缺血再灌注 2h为Bax表达和DNA单链损伤的高峰 。

AIM: To study DNA single strand damage at different time points and expression of Bax in cortical neurons under ischemic like conditions and to investigate the relationship of the expression of Bax and DNA single strand damage. METHODS: The expression of Bax was detected by flow cytometer in cortical neurons under ischemic like conditions. The treated neurons were detected by Klenow method at different time point of reperfusion for the positive expression and a half quantitative analysis was made. RESULTS: 2 hours after reperfusion, the expression of Bax reached peak point and the positive neurons of Bax decreased with the increase of reperfusion time. The average gray of Klenow positive cells with no reperfusion was 72.4±1.0 and increased with the increase of reperfusion time. The highest average gray was 135.5±1.3 at 2 hour of reperfusion. The ratio of Bax positive cells was related to the average gray of Klenow positive cells. CONCLUSION: Under ischemic like conditions, the expression of Bax reaches peak point 2 hours after reperfusion and so is the DNA single strand damage, suggesting that the expression of Bax may be related to the DNA single strand damage.