Autoreceptors
We have so far described transmitter being released by the pre-synaptic neuron, crossing the synaptic cleft, binding to postsynaptic receptors, and shortly afterwards being deactivated. In fact, by no means all receptor sites are located on the post-synaptic membrane. Surprisingly, some axons have receptors for their own neurotransmitter – autoreceptors. For example, there are dopaminergic cells with dopamine autoreceptors on their axons. These can be activated by the dopamine that their own cells release, to provide a local, negative feedback loop, which can inhibit the cell from further firing. So input neurons can modify their own activity while activating their post-synaptic targets.
We have so far described transmitter being released by the pre-synaptic neuron, crossing the synaptic cleft, binding to postsynaptic receptors, and shortly afterwards being deactivated. In fact, by no means all receptor sites are located on the post-synaptic membrane. Surprisingly, some axons have receptors for their own neurotransmitter – autoreceptors. For example, there are dopaminergic cells with dopamine autoreceptors on their axons. These can be activated by the dopamine that their own cells release, to provide a local, negative feedback loop, which can inhibit the cell from further firing. So input neurons can modify their own activity while activating their post-synaptic targets.
No comments:
Post a Comment