David J A, Pitman R M
Gatty Marine Laboratory, School of Biological and Medical Sciences, University of St. Andrews, Fife, UK.
Brain Res. 1995 Jan 9;669(1):153-6. doi: 10.1016/0006-8993(94)01262-g.
The soma membrane of the fast coxal depressor (Df) motoneurone of the cockroach, Periplaneta americana possesses a population of acetylcholine receptors which respond to both nicotinic and muscarinic ligands. Activation of these 'mixed' acetylcholine receptors by McN-A-343 or oxotremorine results in the generation of an inward current at potentials positive to - 40 mV. A large proportion of the outward current induced by membrane depolarization in Df somata is due to a calcium-activated potassium conductance (IKCa) which shows a characteristic N-shape voltage-dependence. This N-shape of the membrane current-voltage relationship is suppressed by McN-A-343 or oxotremorine indicating that the agonist-induced inward current is due to a reduction in IKCa.
美洲大蠊蟑螂快速髋部下压肌（Df）运动神经元的胞体膜具有一群乙酰胆碱受体，它们对烟碱样和毒蕈碱样配体均有反应。McN-A-343或氧化震颤素激活这些“混合”乙酰胆碱受体，会在高于 - 40 mV的电位下产生内向电流。Df胞体中膜去极化诱导的外向电流很大一部分归因于钙激活钾电导（IKCa），它呈现出特征性的N形电压依赖性。McN-A-343或氧化震颤素会抑制膜电流-电压关系的这种N形，表明激动剂诱导的内向电流是由于IKCa的减少。
