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(P0.01). 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(P0.05), and on the 7th, 14th, 21st and 28th day(P0.05). 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.