大鼠脑缺血再灌注后TNF-α、IL-β及细胞间粘附分子-1 mRNA的表达

Expression of TNF-α, IL-β and ICAM-1 mRNA in rats after cerebral ischemia-reperfusion

目的 研究脑缺血再灌注后TNF α、IL β及ICAM 1在mRNA的表达变化 ,以探讨它们在脑再灌注损伤中的作用。方法 提取局灶性脑缺血再灌注大鼠的RNA ,用半定量逆转录 多聚酶链反应 (RT PCR)测定再灌注不同时间点TNF α ,IL β及ICAM 1在mRNA的表达水平。 结果 在缺血侧 ,TNF α和IL βmRNA的表达变化相似 ,缺血及再灌注后表达增加 ,并在再灌注 4h后达到顶峰 ,而ICAM 1mRNA在再灌注 10h后达到顶峰。三类mRNA水平的升高可以保持到再灌注后 3d。在缺血对侧 ,与假手术组比较 ,这三类mRNA水平有所增加 ,但是远远低于缺血侧的mRNA水平。结论 TNF α ,IL β及ICAM 1mRNA在再灌注后不同时间的表达变化表明它们在缺血再灌注损伤中起重要作用。

Objective To investigate the roles of TNF α, IL β and ICAM 1 in brain reperfusion injurby by revealing the time course of their mRNA expression after cerebral ischemia reperfusion. Methods RNA was extracted from rat model of the focal cerebral ischemia reperfusion and mRNA expression levels of TNF α, IL β and ICAM 1 at various time points after reperfusion were measured by semiquantitative reverse transcriptase polymerase chain reaction(RT PCR).Results In ipsilateral hemisphere, the time course of TNF α and IL β mRNA showed similar pattern, their expression increased after ischemia and reperfusion and peaked 4h after reperfusion, while that of ICAM 1 peaked 10h after reperfusion. All three kinds of mRNA levels remained elevated for up to 3d after reperfusion. In contralateral hemisphere, three kinds of mRNA levels increased compared with sham rats, but were consistently lower than those in ipsilateral hemisphere. Conclusion The time course of TNF α, IL β and ICAM 1 mRNA expression revealed here suggested their roles in postischemic reperfusion injury.