| Background and objective: Hypoxic-ischemic brain damage (HIBD) severely impairs the neonates'lives and often results in eternal dysfunctions, which is now scarce of ideal and effective therapy. The studies to adult animals with brain damage indicated that enriched environment could increase neuronal plasticity, improve the brain functions and promote the recovery from brain damage, while the impoverished environment showed the converse effects. However, It's not clearly about the effects and mechanisms of different environment on developmental brain damage. This study was aim to observe the effects of different environment on learning and memory ability and neuronal plasticity of neonatal rats with HIBD, explore the possible neuronal mechanisms, and provide theoretical basis to taking enriched environment as a clinical therapy of neonates with HIBD.Methods: The Sprague-Dawley (SD) rats'models of HIBD were established by the method of Rice. Then the rats with HIBD were divided randomly into 3 groups: enriched environment group (EE), impoverished environment group (IE) and standard environment group (SE). The sham- operation rats served as sham-operation group (Sham). Different environment intervention was administrated to the rats since the 2nd day after HIBD. On the 28th day, Morris water maze was used to evaluate the learning and memory ability. Then the weight and cerebral weight of rats were measured. HE stain and nissl stain were employed to observe the moophorlogical changes and the number of neurons in hippocampus of rats. The immunohistochemical stain and RT-PCR were respectively used to detect the gray values of GAP-43, the number of nestin positive cells and the OD ratio of their mRNA in hippocampus.Results:1. The water maze scores of EE group in place navigation test and spatial probe test were much higher than that of SE group (P<0.01) and IE group (P<0.001), there was no...
|
PDF Full Text Request