presynapsis

例句：

1. 1. The researchers found that the presynaptic activity was responsible for the changes in the brain's electrical activity.
   研究人员发现，前突触活动是大脑电活动变化的原因。
2. 2. During the presynaptic phase, the neurotransmitter is released from the nerve terminal into the synaptic cleft.
   在预突触阶段，神经递质从神经末梢释放到突触间隙。
3. 3. The presynaptic membrane is rich in receptors that respond to various stimuli.
   前突触膜富含各种刺激的受体。