早期丰富环境干预对缺氧缺血性脑损伤新生鼠海马GAP-43表达的影响

目的 探讨早期丰富环境干预对缺氧缺血性脑损伤(hypoxic-ischemic brain injury, HIBI)新生大鼠海马生长相关蛋白(Growth-associated protein-43, GAP-43)表达的影响.方法 按Rice法制备SD大鼠HIBI模型,随机分为干预组和非干预组,假手术大鼠作为对照组.干预组大鼠于HIBI后第2天开始丰富环境干预,分别于术后第3、7、14、21、28天取各组大鼠脑组织进行免疫组织化学染色和RT-PCR检测,观察不同时间点各组大鼠海马GAP-43及其mRNA表达的差异.结果 非干预组大鼠海马GAP-43及其mRNA表达强于对照组(P＜0.01),干预组海马GAP-43表达于术后第14、21、28天强于非干预组,差异显著(P＜0.05),GAP-43mRNA表达于术后第7、14、21、28天强于非干预组,差异显著(P＜0.05). 结论 早期丰富环境干预可以增强HIBI新生大鼠海马GAP-43及其mRNA的表达,提示GAP-43表达的增多可能参与了丰富环境影响HIBI新生大鼠损伤修复的机制.

Effects of early enriched environment intervention on GAP-43 expression in rat hippocampus after hypoxic-ischemic brain injury

Objective To observe the effects of early enriched environment intervention on the expression of growth-associated protein-43(GAP-43) in the hippocampus of rats with hypoxic-ischemic brain injury (HIBI). Methods After the establishment of HIBI model in SD rats by the method of Rice, the animals were divided randomly into 2 groups: the intervention group and non-intervention group. The sham-operation rats were used as control group. Enriched environment intervention had been administrated to the rats of intervention group since the 2nd day after HIBI. On the 3rd, 7th, 14th, 21st and 28th day, immunohistochemistry and RT-PCR were used to measure the expressions of GAP-43 protein and mRNA in the hippocampus of rats. Results The expression of GAP-43 protein and mRNA in the rat hippocampus were increased in the non-intervention group than in the control group(P<0.01). The expressions of GAP-43 protein and mRNA were respectively much higher in the intervention group than in non-intervention group on the 14th, 21st and 28th day(P<0.05), and on the 7th, 14th, 21st and 28th day(P<0.05). Conclusion Early enriched environment intervention can increase the expressions of GAP-43 protein and mRNA in the hippocampus of HIBI rats, indicating that the up-regulation of GAP-43 expression may be associated with the effects of early enriched environment intervention on the rats with HIBI.