Hsu K S, Fu W M, Lin-Shiau S Y
Institute of Pharmacology, College of Medicine, National Taiwan University, Taipei.
Neuropharmacology. 1994 Jan;33(1):35-41. doi: 10.1016/0028-3908(94)90094-9.
The effects of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) on nicotinic acetylcholine (ACh) receptor channels were studied in cultured myocytes of 1-day-old Xenopus embryos. The amplitude and decay time of iontophoretic ACh-induced currents were reduced by MPTP in a concentration-dependent manner. The inhibitory action of MPTP was frequency-dependent, being enhanced by higher frequencies of stimulation at 7 and 30 Hz. Neither pargyline nor tranylcypromine affected the inhibitory effects of MPTP on ACh-induced currents. Single channel recordings showed that MPTP decreased the opening frequency, mean open time as well as the conductance of both low- and high-conductance ACh channels. These results suggest that the inhibitory actions of MPTP on ACh receptor channels in skeletal muscle may contribute to the depression of the nerve-evoked contraction of the mouse diaphragm as previously reported.
在1日龄非洲爪蟾胚胎的培养肌细胞中研究了1-甲基-4-苯基-1,2,3,6-四氢吡啶（MPTP）对烟碱型乙酰胆碱（ACh）受体通道的影响。MPTP以浓度依赖性方式降低了离子电渗法施加ACh诱导电流的幅度和衰减时间。MPTP的抑制作用具有频率依赖性，在7和30Hz的较高刺激频率下增强。帕吉林和反苯环丙胺均不影响MPTP对ACh诱导电流的抑制作用。单通道记录显示，MPTP降低了低电导和高电导ACh通道的开放频率、平均开放时间以及电导。这些结果表明，MPTP对骨骼肌中ACh受体通道的抑制作用可能如先前报道的那样，导致小鼠膈肌神经诱发收缩的抑制。
