中国电鳐胆碱受体的分离及其特性

ISOLATION AND CHARACTERIZATION OF ACTYLCHOLINE RECEPTOR RICH MEMBRANE FROM NARCINE MACULATA

从中国电鳐电器官可分离制备含丰富胆碱受体的粗膜制剂。可用来研究受体与^(131)I-神经毒的结合反应。胆碱受体激动剂、对抗剂对^(131)I-神经毒与受体的结合有竞争性抑制作用,这表明该受体为烟碱样的。该受体似含有两个结合点,其一能与胆碱受体配基相结合,另一能与阳离子相结合。受体与阳离子结合后,可抑制受体与神经毒的结合。广东蛇药同样亦能干扰受体与神经毒的结合反应。并讨论了它的作用机制。

Binding of neurotoxin,labelled with 125I has been studied in crude membrane preparation containing plenty of n-AchR from Narcine electric organ.Competition with a variety of receptor agonist and antagonist indicates that toxin binding exhibits the pattern expected nicotinic acetylcholinc receptor.Membrane bound receptors appear to consist of at least two binding subunits,one for specific cholinergic ligands,and the other appears to preferentially bind to inorganic cations(K^(+),Na^(+),Ca^(2+),Mg^(2+)).After binding with cations,the toxin binding is inhibited.Kwangtung Snake Drug also interferes with toxin-receptor interaction and the mechanism of interference has been discussed.