短暂脑缺血再灌流后ATP含量变化与细胞凋亡的关系

目的:探讨短暂脑缺血再灌流后能量的动态变化及其与细胞凋亡之间的关系。方法:采用线栓法建立大鼠大脑中动脉闭塞(MCAO)模型,缺血10min后于再灌流后0h、1h、3h、6h、12h、24h和72h应用毛细血管电泳法分别测定额顶叶皮质的ATP含量,同时采用荧光显微镜、流式细胞仪和脱氧核苷酸末端转移酶介导的缺口末端标记法(TUNEL)检测细胞凋亡情况,分析两者之间的关系。结果:缺血10min后额顶叶皮质ATP的含量急剧下降至对照组的20%。再灌流后ATP的含量逐渐恢复,于再灌流后1h、3h、6h和12h恢复至对照组的70.5%、65.7%、84.8%和86.9%。再灌流后24hATP含量再次下降,再灌流后24h和72hATP含量仅为对照组的50%,与对照组相比差异有统计学意义(P<0.01和0.05)。缺血10min再灌流24h额顶叶皮质开始出现细胞凋亡现象,并随着时间延长凋亡细胞数目逐渐增加。结论:短暂脑缺血再灌流后大鼠额顶叶皮质存在细胞能量系统功能恢复滞后的现象和继发性细胞能量系统功能衰竭的现象,其中继发性细胞能量系统功能衰竭现象与细胞凋亡之间可能存在互为因果的关系。

Relationship between evolution of ATP content and apoptosis after transient ischemia followed by reperfusion

Objective; To investigate the relationship between the change of energy and the apoptosis after transient ischemia followed by reperfusion. Methods: Rats were subjected to 10 min of middle cerebral artery occlusion (MCAO). At the time point of Oh, 1h, 3h, 6h, 12h, 24h and 72h after reperfusion, ATP content of frontal and parietal cortex were measured by capillary zone electrophoresis. Apoptosis was measured by fluoroscope, flow cytometer and terminal deoxynucleotidyl transferase nediated d-UTP neck end labeling (TUNED methods. Results: At the end of 10 min ischemia, ATP content fell dramatically to less than 20 % of the control level. After reperfusion, ATP content recovered gradually. After 1h, 3h, 6h and 12h of reperfusion, ATP content returned to 70. 5 %, 65. 7 %, 84. 8 % and 86. 9 % of the control level(P = 0. 052, 0. 030, 0. 332 and 0. 491). From 24 h on until 72 h after reperfusion, ATP content deteriorated again, reaching half of the control level(P = 0. 003 and 0. 023). On the other hand, apoptosis occurred from 24 hours after reperfusion on and aggravated with the reperfusion proceeding. Conclusion: The recovery of cellular energy system function was delayed even though the reperfusion is in time after transient cerebral ischemia. Furthermore, secondary failure of cellular energy system function occurred with the reperfusion proceeding. The secondary failure of cellular energy system function and apoptosis interacted mutually.