ACh (Acetylcholine), a chief neurotransmitter of the parasympathetic nervous system is packaged into vesicles by a specific transporter. Then, in a Ca2+-dependent manner, ACh is released from neurons. The transfer of ACh from the cytoplasm into synaptic vesicles is mediated by a specific vesicular ACh transporter (VAChT). Then, the chemical transmitter acetylcholine (ACh) is released into the synaptic cleft as a result of the action potential. The Acetylcholine diffuses across the synaptic cleft and binds to special receptors on the postsynaptic or the postjunctional membrane.