川芎嗪对D-半乳糖损伤模型小鼠学习记忆及胆碱能系统的影响

目的探讨川芎嗪对D-半乳糖(D-galactose,D-gal)损伤模型学习记忆和胆碱能系统功能的影响。方法C57BL/6J小鼠颈背部皮下注射2%D-gal100mg·kg-1·d-1,连续40d制造D-gal损伤模型。第3周起各组分别用生理盐水(正常对照组、模型组)、川芎嗪(高、低剂量组)和哈伯因(阳性对照组)灌胃。第6周起进行Morris水迷宫测试,连续5d。行为测试结束后,进行大脑皮层乙酰胆碱酯酶(acetylcholinesterase,AchE)活性测定和M受体的放射性配基结合分析。结果与正常对照组相比,D-gal模型组学习记忆能力、AchE活性和M受体含量均明显下降(P<0.05),川芎嗪尤其是在100mg·kg-1·d-1剂量时可明显改善学习记忆功能,增强胆碱酯酶活性(P<0.05),上调M受体数目(P<0.005)。结论川芎嗪可明显提高模型小鼠的学习记忆能力,改善中枢胆碱能系统功能。

Effect of tetramethylpyrazine on learning, memory and cholinergic system in D-galactose-lesioned mice

OBJECTIVE: To explore the effect of tetramethylpyrazine on learning, memory, and cholinergic system in D-galactose-lesioned mice. METHODS: C57BL/6J mice were given subcutaneous injection of 2% D-galactose for 40 days (100 mg.kg-1.d-1). Normal saline, tetramethylpyrazine (TMP) and Huperzine A (HupA) were given respectively by intragastric administration in different study groups from the third week on. Learning and memory ability were tested by Morris water maze for 5 days at the sixth week. Acetylcholinesterase (AchE) activity, the binding sites (Bmax) and the affinity (KD) of M-cholinergic receptor were determined. RESULTS: The learning and memory dysfunction, with lowered AchE activity and M-cholinergic receptor binding sites were found in the model group as compared with the normal control group. The tetramethylpyrazine, especially at the dose of 100 mg.kg-1.d-1, could markedly attenuate cognitive dysfunction, while elevate the lowered AchE activity (P < 0.05) and M-cholinergic receptor binding sites (P < 0.005) in the cerebral cortex of mice treated with D-galactose. CONCLUSIONS: The tetramethylpyrazine can significantly improve central cholinergic system function, and thus enhance the learning and memory ability in D-galactose-lesioned mice.