石杉碱甲对乙酰胆碱酯酶活性的抑制作用

Inhibition of Huperzine A on Activity of Acetylcholine Esterase

目的研究石杉碱甲抑制乙酰胆碱酯酶活性的基本特点，为将石杉碱甲用于预防有机磷神经毒剂中毒提供依据。方法以浓度为0，0．2，0．5，0．7，1．0，1．5，2．0，3．0，5．0，10，0mg／kg的石杉碱甲给大鼠灌胃染毒，求得石杉碱甲对大鼠全血、前皮质、小脑、海马乙酰胆碱酯酶活性抑制的剂量～效应曲线；以2mg／kg的石杉碱甲给大鼠灌胃，分别于染毒后0．5，1，2，4，8，12，24h测定乙酰胆碱酯酶活力，求得乙酰胆碱酯酶抑制的时间-效应曲线。结果染毒30min后乙酰胆碱酯酶活性抑制达到高峰，24h后全血及脑组织乙酰胆碱酯酶活力基本恢复正常；0．5～3．0mg／kg石杉碱甲染毒后可获得较合适的预防有机磷神经毒剂中毒的乙酰胆碱酯酶抑制率。绪论石杉碱甲为可逆性乙酰胆碱酯酶抑制剂，可以通过血脑屏障，可能对有机磷类神经毒剂中毒具有预防作用。

Objective To study the basic inhibition feature of huperzine A on the activity of aeetyleholine esterase and provide criteria for huperzine A in preventing organophosphorous nerve intoxicant poisoning. Methods The doses of 0.2, 0.5, 0.7, 1.0, 1.5, 2.0, 3.0, 5.0 and 10.0 mg/kg of huperzine A were used to study the dose-effect relationship of inhibition on aeetyleholine esterase activity of whole blood, frontal cortex, cerebellum, hippocampus in rats. 2.0 mg/kg huperzine A was used to study the time-effect relationship of inhibition on rat aeetyleholine esterase activity after 0.5, 1, 2, 4, 8, 12 and 24 hours exposure. Results The inhibition of acetyleholine esterase activity reached the peak after 0.5 hour and retrieved to normal after 24 hours. The inhibition on aeetyleholine esterase activity obtained by the doses of 0.5-3.0 mg/kg of huperzine A was the appropriate inhibition ratio for preventing organophosphorous nerve intoxicant poisoning. Conclusions Huperzine A is a reversible acetylcholine esterase inhibitor, which could break through the blood brain barrier, and might be effective in preventing organophosphorous nerve intoxicant poisoning.