Synonyms
Ligand-gated ion channel; Receptor channel
Definition
Ionotropic receptors are membrane-spanning protein complexes that direct the coupling of the neurotransmitter receptor to the ion channel. They contain two functional domains: an extracellular site that binds neurotransmitters and a membrane-spanning domain that forms an ion channel. The neurotransmitter binding to the ionotropic receptor leads to a conformational change that is passed along to the closely associated ion channel, and as a result the channel properties are altered. This important feature of ionotropic receptors means that the modulation of ion channel properties varies with the length of time that the transmitter occupies the receptor. Therefore they mediate rapid-onset and rapidly reversible synaptic transmission, generally in millisecond orders. In contrast, the activation of metabotropic receptors produces much slower responses, ranging from hundreds of milliseconds to minutes or even longer. Ionotropic...
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Sakimura, K. (2009). Ionotropic Receptor. In: Binder, M.D., Hirokawa, N., Windhorst, U. (eds) Encyclopedia of Neuroscience. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-29678-2_2596
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DOI: https://doi.org/10.1007/978-3-540-29678-2_2596
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