葛根素对D-半乳糖致衰老小鼠记忆行为和海马突触结构的影响

目的　探讨葛根素对D 半乳糖致衰老小鼠记忆行为的影响及其脑内突触机制。方法　用开场行为和Y 迷宫分辨学习记忆行为分别检测ip不同剂量葛根素后衰老模型小鼠自发活动和学习记忆行为的变化 ,然后用电镜和计算机图象分析仪观测小鼠海马CA3区GrayI型突触界面结构参数的变化。结果　葛根素 60mg·kg- 1 可显著增加D 半乳糖致衰老小鼠在新异环境中的自发活动和探究行为 ,显著提高其学习记忆能力 ;同时使衰老小鼠海马突触后致密物质 (PSD)厚度显著增加 ,突触间隙宽度显著减小。结论　葛根素对D 半乳糖致衰老小鼠学习记忆能力的改善作用可能与其改变海马突触界面结构有关

EFFECT OF PUERARIN ON LEARNING-MEMORY BEHAVIOR AND SYNAPTIC STRUCTURE OF HIPPOCAMPUS IN THE AGING MICE INDUCED BY D-GALACTOSE

AIM: To study the effects of puerarin on learning-memory behavior of aging mice induced by D-galactose and its possible mechanism of action. METHODS: The aging mice were induced by s.c. 0.12 g.kg-1 D-galactose for 6 weeks. The aging mice were treated with three doses of puerarin once a day for 5 weeks. The spontaneous behavior and the learning memory behavior were tested in the aging mice using open field and Y-maze at the next day after the last treatment. The structure of Gray I synaptic interface in the CA3 area of the hippocampus was quantitatively analyzed by electronic microscope and computer image processing appliance. RESULTS: Compared with the D-galactose control group, puerarin (60 mg.kg-1) was shown to increase significantly the spontaneous behavior and explorative response in the open field, and improve remarkablely the learning and memory ability of the aging mice induced by D-galactose. Meanwhile, the thickness of post-synaptic density (PSD) was increased, and the width of the synaptic cleft in the hippocampus CA3 area was shortened. CONCLUSION: Puerarin showed an improvement effect against the memory impairment in the modelling aging-mice induced by D-galactose. A pathological alteration of synaptic interface structure in hippocampus of the mice may be involved in the effect.