PTX-sensitive and -insensitive synaptic modulation at the frog neuromuscular junction.
PTX-sensitive and -insensitive synaptic modulation at the frog neuromuscular junction.
复制标题
青蛙神经肌肉接头处的 PTX 敏感和不敏感突触调节。
DOI：
10.1097/00001756-200009110-00038
复制
发表时间：
2000
期刊：
影响因子：
1.7
通讯作者：
Ko,CP
中科院分区：
文献类型：
--
作者：
Sugiura,Y;Ko,CP
药理学操作被用来检查G蛋白在调节青蛙神经肌肉接头突触传递中的作用。G蛋白拮抗剂百日咳毒素（PTX）可增加终板电位（epp）的振幅，但对微终板电位的振幅和频率无影响。G蛋白激动剂Mastoparan降低epp振幅，而拮抗剂苏拉明增加epp振幅。结果表明，PTX敏感的G蛋白通过减少突触前动作电位释放的递质量来调节突触传递。我们还发现，内源性ATP减少递质释放通过P2受体在PTX不敏感的方式。因此，至少有两种不同的机制调节神经肌肉传递;一种与PTX敏感的G蛋白偶联，另一种则不然。
Pharmacological manipulations were used to examine the role of G proteins in modulating synaptic transmission at the frog neuromuscular junction. Pertussis toxin (PTX, a G protein antagonist) increased end-plate potential (epp) amplitude but had no effect on the amplitude or frequency of miniature end-plate potentials. Mastoparan (a G protein agonist) decreased epp amplitude, while suramin (an antagonist) increased epp amplitude. The results suggest that PTX-sensitive G proteins tonically modulate synaptic transmission by reducing the amount of transmitter released in response to presynaptic action potentials. We also showed that endogenous ATP decreased transmitter release via P2 receptor in a PTX-insensitive manner. Thus, at least two distinct mechanisms regulate neuromuscular transmission; one is coupled to PTX-sensitive G proteins and the other is not.