摘要
目的观察脑缺血预处理对新生Wistar大鼠海马CA1区缺氧诱导因子-1(HIF-1)mRNA表达的影响,以及在缺氧缺血脑损伤内源性保护机制中的作用。方法通过阻断7日龄新生Wistar大鼠右侧颈总动脉制备脑缺血模型,设置假手术组、缺血再灌注组和预缺血-缺血再灌注组;应用原位杂交方法和计算机图像分析技术检测新生鼠脑缺血再灌注后不同时点脑组织HIF-1mRNA的表达。结果预缺血-缺血再灌注组和缺血再灌注组于再灌注3h后HIF-1mRNA表达开始增多,以预缺血-缺血再灌注组升高更明显,12h开始下降,三组间比较差异有统计学意义(P<0.05),24h后降至假手术组水平。预缺血-缺血再灌注组脑神经细胞有轻微水肿和少量神经细胞坏死,缺血再灌注组以神经细胞坏死为主。结论脑缺血再灌注早期可诱导神经细胞HIF-1mRNA表达增多;经脑缺血预处理后HIF-1mRNA表达较单纯脑缺血再灌注组升高更明显;HIF-1表达可能与脑缺血后神经细胞的内源性保护机制有关,脑缺血预处理对再次严重的脑缺血有保护作用。
Objectives To determine the mRNA expression of hypoxia-inducible factor-1 （HIF-1） in hippocampal CA1 region after cerebral ischemia-reperfusion in 7 day-old Wistar rats with cerebral ischemic preconditioning and investigate the neuroprotective effect and mechanism in newborn rats with hypoxic-ischemic brain damage. Methods Cerebral ischemia in 7 day-old Wistar rats was induced by occluding the right carotid artery for 45 minutes. The newborn Wistar rats were randomly divided into sham-operated group, ischemia-reperfusion group and preischemia-reperfusion group. In situ hybridization was used to detect the expression of HIF-1 mRNA in the hippocampal CA1 region. Resuits ①The expression of HIF-1mRNA in hippicampal CA1 region in both ischemia-reperfusion group and preischemia-reperfusion group were significantly increased and peaked at 3 h, then decreased at 12 h after reperfusion. The corrected-optical-density of the preischemia-reperfusion group was significantly higher than the other two groups, with a statistical significance at 3 h and 12 h, compared with both sham-operated group and ischemia-reperfusion group. The expression dropped back to similar levels as in the sham-operated group after 24 h; ②The histopathological manifestation of the brain damage in the preischemia-reperfusion group was milder than that of the ischemia-reperfusion group. There was mild edema and neuronal cell death in the preischemia-reperfusion group while mainly neuronal cell death was observed in the ischemia-reperfusion group. Conclusions At the early stage after ischemia-reperfusion, there was increased expression of HIF-1 mRNA in the hippicampal CA1 region. This increase in expression was more significant in the preischemia-reperfusion group than in the ischemia-reperfusion group. It is suggested that the expression of HIF-1 mRNA in the hippicampal CA1 region may be involved in the endogenous protective mechanism after cerebral ischemia-reperfusion. It could provide protective effects for serious brain damage by cerebral isc
出处
《临床儿科杂志》
CAS
CSCD
北大核心
2007年第6期484-487,共4页
Journal of Clinical Pediatrics
基金
贵州省科技厅资助项目[No.(2003)3041]
