西红花苷对阿尔茨海默病大鼠学习记忆及海马LTP的影响

Effects of Crocin on Spatial Learning and Memory and LTP in Hippocampus on Rats with Alzheimer disease

目的:探讨西红花苷对阿尔茨海默病(Alzheimer’s disease,AD)大鼠空间学习记忆能力对海马LTP的影响。方法:健康成年SD大鼠,随机分为正常对照组、AD模型组、西红花苷(低、中、高剂量)组Morris水迷宫实验检测空间学习记忆能力,电生理实验检测海马LTP,Western Blot检测海马GAP-43蛋白表达。结果:AD模型组大鼠寻找水下平台的潜伏期时间较对照组延长(P<0.01),西红花苷各剂量组寻找水下平台的潜伏期时间从第二天起,较AD模型组均缩短(P<0.01),西红花苷中剂量组和高剂量组的潜伏期时间均短于低剂量组(P<0.05),中、高剂量组间的潜伏期时间在各实验日均未见有无显著性统计学差异。强直性高频刺激海马诱发电位的幅值比较,AD模型组低于对照组(P<0.01),西红花苷各剂量组高于AD模型组(P<0.05),且西红花苷中、高剂量组高于低剂量组(P<0.05)。西红花苷各剂量组海马GAP-43表达低于对照组(P<0.01),高于AD模型组(P<0.01)。结论:西红花苷对AD大鼠学习记忆能力有一定改善作用,增强海马LTP和GAP-43的表达。

Objective： To investigate the effect of Crocin on spatial learning and memory and LTP in hippocampus on rats with Alzheimer＇s disease. Methods： Healthy adult SD rats were randomly divided into five groups： control group,AD model group,and crocin（ low,medium,high） dose group. Morris water maze（ MWM） test was used to detect the spatial learning and memory,the effect of long-term-potentiation（ LTP） was detected in the Electrophysiological experiment,and expression of GAP-43 protein in hippocampus was examined by Western Blot. Results： The latency of rats in searching for the underwater platform in AD moodle group was longer compared with the control（ P〈0. 01）,the latency in the Crocin groups was shorter compaerd with the AD model group from the second test day（ P〈0. 01）. In crocin groups,the latency in the medium and high dose groups were shorter than the low-dose group（ P〈0. 05）,but there was no remarkable difference in the latency between the medium dose group and the high dose group in all test days. The amplitude of the evoked potential of AD model group was lower than the control group（ P〈0. 01）,the crocin groups were higher than that in AD model group（ P〈0. 05）,and the midium and high dose group of crocin were higher than the low dose group（ P〈0. 05）. The expression of GAP-43 in each crocin dose group decreased compared with that of the control group（ P〈0. 01）. It increased compared with that of the AD model group（ P〈0. 01）. Conclusion： Crocin could im-prove the spatial learning and memory ability of AD rats,and enhance LTP,and expression of GAP-43 in hippocampus.