Autoreceptors

An autoreceptor is a receptor located on presynaptic nerve cell terminals and serves as a part of a feedback loop in signal transduction. It is sensitive only to those neurotransmitters or hormones, that are released by the neuron in whose membrane the autoreceptor sits.

Canonically, a presynaptic neuron releases the neurotransmitter across a synaptic cleft to be detected by the receptors on a postsynaptic neuron. An autoreceptor will detect this neurotransmitter from its position on the presynaptic membrane. For example, presynaptic NMDA receptors are sensitive to glutamate released from presynaptic vesicles.

Autoreceptors usually do not generate changes in membrane potential. Instead, they often function to control internal cell processes, including synthesis and release of the neurotransmitter.