摘要
在非洲爪蟾胚胎神经和肌肉细胞上，用膜片钳技术研究了有机磷杀虫剂氧化乐果对烟碱样乙酰胆碱受体（ｎＡＣｈＲ）离子通道的作用，发现它对自发微终板电流（ＭＥＰＣ）有双重作用，低浓度（８．６４μｍｏｌ·Ｌ－１）增加其幅度和频率，高浓度（３０．１６μｍｏｌ·Ｌ－１）则相反．６５９μｍｏｌ·Ｌ－１氧化乐果缩短通道开放时间，降低开放概率，对ｎＡＣｈＲ通道电流幅度和细胞膜钠，钾通道电流无影响．提示氧化乐果为ｎＡＣｈＲ离子通道开放阻断剂．本实验从分子水平上为有机磷杀虫剂对ＡＣｈＲ的直接作用提供了依据．
Patch clamp technique was used to study the inhibitory effect of omethoate, an organophosphorous pesticide, on the membrane of embryonic Xenopus muscle cells in culture. By whole cell clamp and cell attached clamp, we found that both miniature end plate current (MEPC) and single channel current were directly inhibited by omethoate. Omethoate increased the amplitude and frequency of MEPC at a lower concentration (8.64 mol·L 1 ) and decreased them at a higher concentration (30.16 mol·L 1 ). The omethoate at a concentration of 659 mol·L 1 shortened the opening time and decreased the opening probability of the single channel. This result shows that omethoate is an AChR channel opening blocker.
出处
《中国药理学与毒理学杂志》
CAS
CSCD
北大核心
1997年第4期286-290,共5页
Chinese Journal of Pharmacology and Toxicology
基金
卫生部重点研究课题
关键词
氧化乐果
烟碱
乙酰胆碱受体
离子通道
NACHR
organophosphorous compounds
receptors, acetylcholinergic
patch clamp
Xenopus laevis
