Holman M E, Weinrich J P
Pflugers Arch. 1975 Oct 28;360(2):109-19. doi: 10.1007/BF00580534.
The membrane potential of smooth muscle cells in the circular layer of the guinea pig ileum was recorded using intracellular electrodes. Transmural stimulation, in the presence of atropine, caused a transient hyperpolarization, an inhibitory junction potential (IJP). IJP's are thought to result from the action of transmitter released from intramural inhibitory nerves. It has been reported that, in the guinea pig jejunum, the amplitude of the IJP resulting from field stimulation is not altered by changes in the calcium and magnesium ion concentration in the bathing solution. Experiments reported here have shown that the IJP amplitude decreased markedly on reducing the calcium ion concentration and or increasing the magnesium ion concentration. Indirect evidence is presented suggesting that the decrease in amplitude of the IJP is due to a decrease in the amount of transmitter released.
使用细胞内电极记录豚鼠回肠环形肌层平滑肌细胞的膜电位。在阿托品存在的情况下进行跨壁刺激，会引起短暂的超极化，即抑制性接头电位（IJP）。IJP被认为是由壁内抑制性神经释放的递质作用所致。据报道，在豚鼠空肠中，场刺激引起的IJP幅度不会因浴液中钙和镁离子浓度的变化而改变。此处报道的实验表明，降低钙离子浓度和/或增加镁离子浓度时，IJP幅度会显著降低。提出的间接证据表明，IJP幅度的降低是由于递质释放量的减少。
