Chapter 10 - Neurotransmitter Receptors

Abstract

Chemical transmission is the fundamental mode of communication in the nervous system that depends on receptors in the plasma membrane for sensing released neurotransmitter and for producing an appropriate, well-timed response. Two distinct types of receptors mediate this process: ionotropic and G-protein coupled. Ionotropic receptors are protein complexes and, through transmitter binding, conformational changes are induced that directly open a pore to permit ion flow. Ionotropic receptors produce the majority of excitatory and inhibitory signals required for rapid signaling in the central and peripheral nervous system. G-protein coupled receptors (GPCRs) are monomeric or dimeric complexes that mediate their effects by coupling to G-proteins when bound to transmitter. GPCRs typically produce slower onset and longer duration responses because their activation often leads to a series of enzymatic steps that alter the metabolism of the cell. The structure and function of these receptor molecules is the focus of this chapter.