天麻素对血管性痴呆大鼠学习记忆能力和海马p53表达的影响

目的：探讨天麻素对血管性痴呆（VD）大鼠学习记忆能力和海马p53表达的影响。方法：将大鼠随机分成模型组、对照组、治疗组（高剂量天麻素组和低剂量天麻素组）,采用改良Pulsinelli四血管闭塞法（4-VO）建立VD大鼠模型,天麻素高剂量组模型大鼠用天麻素80 mg.kg^-1.d^-1灌胃,天麻素低剂量组模型大鼠用天麻素40 mg.kg^-1.d^-1灌胃,连续4周。水迷宫检测各组大鼠学习记忆能力,免疫组织化学检测大鼠海马p53免疫反应阳性细胞表达。结果：与VD模型组比较,天麻素治疗后VD大鼠学习记忆能力明显提高,海马p53免疫阳性神经元明显减少（P〈0.01）,以高剂量天麻素组效果更显著。结论：天麻素可改善VD大鼠学习记忆能力,其机制可能与下调p53表达、抑制缺血海马神经细胞的凋亡有关。

The Effect of Gastrodine on Learning Capability,Memory and p53 Expression in Hippocampus of Vascular Dementia Model Rats

Objective： To study the effect of gastrodine on learning capability, memory and expression of p53 in hippocampus of vascular dementia （VD） model rats. Methods ： The experimental rats were randomly divided into four groups： VD model group （group V）, control group （group C）, and high dose （group H） and low dose （group L） of gastrodine treatment groups. VD models were established with improved Pulsinelli four vessel occlusion （4-V0）method. Gastrodine was administered intragastrically with doses of 80 mg · kg^-1· d ^-1 and 40 mg · kg^-1 · d^-1 to rats in groups H and L respectively daily for 4 weeks. Learning and memory abilities of rats in 4 groups were evaluated with Morris Water Maze test, and the expressions of p53 proteinum in hippocampus dentate gyrus （HDG） were examined by immunohistochemistry method. Results： The learning and memorizing abilities were significantly improved in groups H and L compared with those of group C. Expression of p53 was lower in both treatment groups, than that of group C （ P 〈0.01 ） , and treatment of high dose gastrodine was even more effective. Conclusions： Gastrodine can improve the learning and memorizing abilities of VD model rats. The down-regulation of p53 and inhibition of isehemia hippocampus nerve eell apoptosis might be potential mechanism for the improving effects of gastrodine.