Mechanism of action of the nicotinic acetylcholine receptor.

Nicotinic acetylcholine receptors at peripheral synapses mediate rapid and effective excitatory synaptic transmission. The functional properties of peripheral and central nicotinic acetylcholine receptors are similar, yet in the central nervous system nicotinic receptors do not appear to occur postsynaptically at many excitatory synapses. Two properties of nicotinic receptors are that significant Ca2+ influx can occur through the receptor channel and that at low agonist concentrations steady activation of nicotinic receptors can occur. These are discussed in the context of presynaptic and postsynaptic localizations of nicotinic receptors.