亚低温对鼠脑梗塞灶周边葡萄糖利用率的影响

Effects of Mild Hypothermia on the Glucose Utilization in the Aroud Area of Infarction in Rats’ Brain

目的 :观察亚低温治疗对大鼠局灶性脑缺血再灌注模型梗死灶周边葡萄糖利用率 (localcerebralglucoseutilization ,LCGU)的影响 ,探讨其脑保护机制。方法 :8只大鼠随机分为对照组、亚低温组。采用大鼠大脑中动脉脑缺血 (middlecerebralarteryocclusion ,MCAO)再灌注模型 ,缺血 3h再灌注 2 1h。缺血 2 4h后处死动物 ,采用定量放射自显影技术测定各组缺血侧大脑半球缺血中心、梗死灶周边区及对侧大脑半球同源区的LCGU。结果 :与对侧同源区比较 ,两组皮质梗死灶周边LCGU未见升高 ,而两组皮质下梗死灶周边均有一LCGU升高区 (P <0 .0 5 ) ,但亚低温组LCGU升高显著低于对照组 (P <0 .0 5 )。与对照组比较 ,亚低温组对侧大脑同源区的LCGU明显低 (P <0 .0 5 )。结论 :再灌注期亚低温降低葡萄糖代谢率 ,减少能量消耗。

Objective: To investigate the effects of mild-hypothermia on local cerebral glucose utilization (LCGU)of infarctional rim in the rat models of focal cerebral ischemia. Methods: 8 rats were randomly divided into control group and mild-hypothermia group. Focal cerebral ischemia and reperfusion model was induced by middle cerebral artery occlusion(MCAO). After 3h of ischemia,cerebral blood flow was restored by releasing the occlusion of internal carotid artery(ICA). After 24 hours ischemia,autoradiographic studies of 14 C-2-deoxyglucose( 14 C-DG) were performed to measure local cerebral glucose utilization rate in the boundary zone around ischemic core. Results: LCGU had not increasen in the periphery zone around cortex infarction. A dramatical increase of LCGU was observed in the boundary zone around subcortex infarction in control group and in mild hypothermia group. However,in hypothermia group,the increase of LCGU was suppressed remarkably. Moreover,LCGU of contralateral globe in the hypothermia group was lower than that in control group(P<0.05). Conclusion: Mild hypothermia induced in reperfusion period suppresses glucose metabolism and reduces energy consumption.