Presynaptic receptors and modulation of the release of noradrenaline, dopamine and GABA.

A review of the role of presynaptic receptors in the modulation of neurotransmitter release indicates two types of presynaptic receptors. By means of presynaptic inhibitory autoreceptors a neurotransmitter can regulate its own release. In addition, presynaptic receptors are acted upon by other endogenous compounds, either transmitters released from adjacent nerve terminals, blood-borne compounds or locally-formed substances, involved in trans-synaptic feed-back. Both types of presynaptic receptors may be involved in the physiological control of transmitter release and are the target of drug action, either as agonists or as antagonists.