When an action potential comes down this pre-synaptic axon, when it reaches this point here, it sets off the process of these vesicles dumping their content into the synaptic cleft.

当动作电位到达轴突的突触前膜时,当到达这一点时 小泡就将其内含物,排放到突触间隙中去

耶鲁公开课 - 生物医学工程探索课程节选

another thing that you'd find if you looked inside the axon terminals of any of these pre-synaptic membranes, you'd find lots of vesicles or some membrane bound compartments that contain special chemicals called neurotransmitters.

如果你仔细观察,突触前膜的轴突末梢内部,你会发现很多小泡,即膜包被的结构,包含有称为神经递质的特殊化合物

耶鲁公开课 - 生物医学工程探索课程节选