1. Calcium (Ca2+)is a vital element in the process of neurotransmitter release; when Ca2+channels are blocked, neurotransmitter release is inhibited.
2. These consist of multi-protein complexes that tether the synaptic vesicle to the presynaptic membrane and contain high concentrations of voltage-gated calcium channels.
3. This leads to brisk calcium influx in response to axon terminal depolarization, since the concentration of calcium is 10,000 times higher in the extracellular fluid.