Anticholinesterase effects of huperzine A,E2020,and tacrine in rats

目的：比较石杉碱甲、Ｅ２０２０和他克林对大鼠胆碱酯酶的抑制作用．方法：比色法测定大鼠各脑区的ＡＣｈＥ及血清中ＢｕＣｈＥ活力．结果：三药灌胃后对大鼠脑中ＡＣｈＥ均产生剂量依赖性抑制．以石杉碱甲作用最强．他克林对ＢｕＣｈＥ的抑制显著强于Ｅ２０２０和石杉碱甲，其副反应最为明显．单次经口给药后，石杉碱甲对脑内ＡＣｈＥ的抑制作用长于Ｅ２０２０和他克林．多次给药后，对胆碱酯酶的抑制作用三药均未有耐受性产生．结论：石杉碱甲是一种高选择性ＡＣｈＥ抑制剂，具有口服活性高，作用时程长，副反应小的优点，适于临床应用．

AIM: To compare the anticholinesterase effects of huperzine A (Hup A), E2020, and tacrine in rats. METHODS: Spectrophotometry was used to determine AChE activity in brain and BuChE activity in serum. RESULTS: Following intragastric gavage, Hup A, E2020, and tacrine all produced dose dependent inhibitions of brain AChE. Oral Hup A exhibited a higher inhibition than E2020 and tacrine. Tacrine was more effective in inhibiting serum BuChE correlated with severe peripheral adverse effects. The BuChE activity was less affected by Hup A and E2020. After a single oral dose of Hup A, a relatively steady state of AChE inhibition produced, which was longer than that after E2020 and tacrine. No change in the cholinesterase inhibition was seen for the 3 drugs following repeated ig medications. CONCLUSION: Hup A ig exhibited a higher efficacy, a longer duration of action, and a more selective inhibition on AChE than E2020 and tacrine.