动作电位到达神经末梢 ACETYLCHOLINE BINDS+ TO RECEPTOR SITES →接头前膜去极化 amically-regulated ion channels on motor end plate →电压门控Ca2+通道开放 →Ca2+内流 →>接头前膜内[Ca2+]升高 Acetylchol →突触小泡与接头前膜融 Sodium ion ynaptic cleft Acetycholine eptor site 合,将ACh排放到接头间隙 regulated ion channel Inside of 量子式释放( quantal Potassium ion muscle cell release)动作电位到达神经末梢 → 接头前膜去极化 →电压门控Ca2＋通道开放 → Ca2＋内流 → 接头前膜内[Ca2＋] 升高 → 突触小泡与接头前膜融 合，将ACh排放到接头间隙。 量子式释放(quantal release)