亚低温干预联合青皮升压对局灶性脑缺血再灌注损伤的保护作用及相关机制探讨

The protective effects and mechanism of Green Tangerine induced hypertension and mild hypothermia on brain infarction during focal cerebral ischemia and reperfusion

目的观察中药青皮联合亚低温干预对大鼠局灶性脑缺血再灌注模型的保护作用及对脑梗死灶周边葡萄糖利用率(LCGU)的影响,同时探讨其相关的脑保护机制。方法将64只实验大鼠随机分为对照组、青皮升压组、亚低温组及亚低温+升压组。将上述4组大鼠制成局灶性脑缺血再灌注模型,其中青皮升压组于缺血再灌注后给予升压干预,亚低温组于缺血再灌注后给予亚低温治疗,亚低温+升压组于缺血再灌注后同时给予升压及亚低温处理,对照组则未给予特殊处理。观察各组实验大鼠神经功能缺损评分、脑梗死灶体积及缺血侧大脑半球梗死灶周边区LCGU水平的变化情况。结果青皮升压组、亚低温组及亚低温+升压组大鼠神经功能缺损评分、脑梗死灶体积、LCGU水平均明显低于对照组(均P<0.05);亚低温+升压组大鼠脑梗死体积、LCGU水平明显低于青皮升压组及亚低温组(均P<0.05)。结论升压及亚低温干预措施均对局灶性脑缺血再灌注损伤具有明显脑保护作用,两者联用具有协同功效,能进一步提高疗效,其相关治疗机制可能包括升压及亚低温协同治疗能改善缺血半暗带区局部脑血流量与LCGU不匹配的现象。

Objective To investigate the protective effects of Green Tangerine induced hypertension and mild hypothermia on focal cerebral ischemia and reperfusion and local cerebral glucose utilization （LCGU） in the infarction rim in rats. Methods A total of 64 rats were used and randomly divided into a control group, a Green Tangerine induced hypertension group, a mild hypothermia group and a combination therapy group. The neurologic deficits, infarct size and LCGU were observed in the rats with focal cerebral ischemia and reperfusion. Results Compared with the control group, the neurologic deficits （ P 〈 0.05 ） , infarct size （ P 〈 0.01 ） and LCGU （ P 〈 0.01 ） were significantly lower in all treatment groups, the infarct size and LCGU of the combination therapy groups were lower than that of the hypertension group and mild hypothermia group （P 〈0.05）. Conclusion Hypertension and mild hypothermia could provide cerebral protective effects during focal cerebral ischemia and reperfusion, and combination of mild hypothermia and hypertension therapy had greater protective effect than monotherapy. The protective mechanism might be attributed to the improvement of the disorder of rCBF and LCGU in the infarction rim synergetically caused by mild hypothermia and hypertension.