摘要
目的:比较石杉碱甲,他克林和E2020对胆碱能传递的作用.方法:在小鼠的膈神经肌肉标本上用胞内记录的方法研究了石杉碱甲(HupA),他克林(tacrine)和E2020对自发释放的小终板电位(MEPP),终板电位(EPP)的量子含量,以及肌细胞的静息膜电位的作用.结果:HupA,tacrine和E202010μmol·L-1可增强MEPP的振幅、上升相和半下降相,其作用强度为E2020>HupA>tacrine.HupA对MEPP的频率,以及gMEPP和sMEPP的出现率无显著影响.它对EPP的量子含量和肌细胞的静息膜电位亦无显著作用.结论:HupA是一种高选择性的AChE抑制剂,由此促进神经肌肉接头处的胆碱能传递.
AIM: To compare the effects of huperzine A (Hup A), tacrine, and E2020 on cholinergic transmission at mouse neuromuscular junction in vitro. METHODS: The isolated mouse phrenic nerve-hemidiaphragm preparations were used with the conventional intracellular recording technique. The miniature end-plate potentials (MEPP), the mean quantal content of end-plate potentials (EPP), and the resting membrane potentials of muscle fiber were recorded. RESULTS: Hup A, tacrine, and E2020 at the concentration of 1.0 mu mol . L(-1) increased the amplitude, time-to-peak, and half-decay time of MEPP in the potencies of E2020 > Hup A > tacrine. Hup A did not significantly change the frequency of MEPP, the appearance of giant MEPP or slow MEPP, the resting membrane potentials, and the mean quantal content of EPP. CONCLUSION: Hup A is a selective and potent cholinesterase inhibitor, by which activity it facilitates the cholinergic transmission at mouse neuromuscular junction, and devoid of pre- and post-synaptic actions.
出处
《中国药理学报》
CSCD
1997年第1期6-10,共5页
Acta Pharmacologica Sinica
关键词
石杉碱甲
他克林
神经肌肉接头
胆碱酯酶抑制剂
cholinesterase inhibitors
huperzine A
tacrine
E2020
neuromuscular junction
diaphragm
phrenic nerve
electrophysiology