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

In some cells they're recycled, that is the cell is able to take up the neurotransmitter after it's released and restore it, but most often there are enzyme systems inside the pre-synaptic membrane where those neurotransmitters are synthesized.

在一些细胞中神经递质可以循环利用,这些细胞可以吸收,已经释放出的神经递质并重新储存起来,但更常见的是突触前膜中含有酶系统,在此合成神经递质

耶鲁公开课 - 生物医学工程探索课程节选