摘要
目的对比研究不同时期亚低温（ＭＨＴ３２℃±０．２℃）对局灶脑缺血再灌注损伤的作用。方法６４只雄性ＳＤ鼠被随机分成常温（ＮＴ）、缺血期亚低温（ＭＨＴｉ）、再灌注期亚低温（ＭＨＴｒ）、缺血期加再灌注期亚低温（ＭＨＴｉ＋ｒ）四组，并用改良Ｋｏｉｚｕｍｉ＇ｓ局灶脑缺血模型，分别观察了动物缺血３小时再灌注３小时过程中，缺血周边和核心区局部脑血流（ｒＣＢＦ）改变，再灌注３小时后血脑屏障（ＢＢＢ）破坏及再灌注７２小时后缺血梗塞灶体积。结果ＭＨＴｉ＋ｒ及ＭＨＴｉ均有改善缺血周边区再灌注后急性高灌注和继发低灌流及核心区持续低灌流、减轻血脑屏障破坏、减少缺血梗塞灶体积的作用。该作用尤以ＭＨＴｉ＋ｒ为明显。ＭＨＴｒ作用有限。结论ＭＨＴｉ＋ｒ对皮层的保护作用较ＭＨＴｉ好。由此可推知，局灶脑缺血再灌注损伤是个持续的过程，亚低温治疗不但要考虑开始时间。
Objective To compare the effects of mild hypothermia(MHT 32℃±0 2℃) induced in different time courses of cerebral ischemia and reperfusion. Methods 64 male SD rats were divided into three mild hypothermic groups, which including intra ischemia(MHTi), intra reperfusion(MHTr), intra ischemia/reperfusion(MHTi+r) group, and one normothermic group(NT 37℃±0 2℃) as control. Reversible focal ischemia was carried out in rats with modified Koizumi's model. Cortical blood flow was measured during 3hr of ischemia following 3hr of reperfusion. The permeability of blood brain barrier(BBB) was estimated after 3hr of ischemia and 3hr of reperfusion. The infarct volume was measured at 72hr after reprefusion. Results The acute postischemic hyperperfusion and delayed hypoperfusion in ischemic perifocal region and sustained hypoperfusion in ischemic core were inhibited in both MHTi+r and MHTi groups. The disruption of BBB and the infarct volume in the basal ganglia and cortex regions were significantly less in both MHTi+r and MHTi groups, especially in the MHTi+r group. The effect of MHTr on prolonged ischemia/reperfusion injury was limited. Conclusion This study demonstrated that MHTi+r has more substantial protective effects on reducing ischemia/reperfusion injury than MHTi. These differences between MHTi and MHTi+r suggest that ischemic and reperfusional injury is an ongoing process, and the concept of MHT therapeutic window must include not only the time of initiating but also the duration of the intervention.
出处
《中华神经外科杂志》
CSCD
北大核心
1999年第1期31-34,共4页
Chinese Journal of Neurosurgery
关键词
脑缺血
再灌注损伤
亚低温
保护作用
Focal cerebral ischemia Reperfusion injury Mild hypothermia
