雌激素对血管性痴呆大鼠学习记忆功能和海马p53、超氧化物歧化酶表达的影响

Effects of estrogen on learning and memory ability, and hippocampal p53 and superoxide dismutase expression in rats with vascular dementia

目的 观察雌激素对血管性痴呆大鼠学习记忆功能和海马p53、超氧化物歧化酶（SOD）表达的影响.方法 将60只SD大鼠随机分成4组.对照组和模型组腹腔注射生理盐水,雌激素高、低剂量组注射雌激素2 mg/kg和1 mg/kg.8周后测试学习记忆能力和海马p53、SOD表达.结果 与雌激素低剂量组大鼠比较,雌激素高剂量组大鼠的逃避潜伏期、第三象限活动时间、穿越站台均明显减少（P＜0.05）.雌激素低剂量组p53平均吸光度（IA）值为0.25士0.01,雌激素高剂量组p53 IA值为0.30±0.02,差异有统计学意义（P＜0.05）.结论 雌激素显著下调p53促凋亡基因,提高SOD的活力,对海马区的神经元起到了保护作用.

Objective To explore the effects of estrogen on learning and memory ability,and hippocampal p53 and superoxide dismutase （SOD） expression in rats with vascular dementia.Methods Sixty rats were randomly divided into four groups,and given estrogen or normal saline for 8 weeks.Morris water maze test was used to measure the learning and memory ability,and the expression of p53 protein and SOD activities were examined in the hippocampus.Results As compared with the low dose estrogen group,the escape latency of rats,the Quadrant Ⅲ activity time and the number of cross platform were significantly shortened in the high dose estrogen group at the first day （P 〈0.05）.The expression of hippocampal p53 （0.25 ± 0.01） in the low dose estrogen group was significantly lower than that in high dose estrogen group （0.30 ± 0.02）.Conclusion Estrogen decreases the expression of p53 protein and enhance the activity of SOD.It can protect the hippocampus related to the memory ability.