Serotonin 5-HT3, 5-HT4, and 5-HT-M receptors.
Serotonin (5-hydroxytryptamine [5-HT]) receptors can be classified either pharmacologically, into 5-HT1, 5-HT2, 5-HT3 and 5-HT4 receptors, or functionally, into G-protein-coupled receptors (5-HT1, 5-HT2, and 5-HT4) and ligand-gated ion channels (5-HT3). This article concentrates on the pharmacology, distribution, receptor-effector coupling, possible subtypes, and species differences of 5-HT3 receptors, which are equivalent to Gaddum and Picarelli's 5-HT-M receptor. Also presented here are some of the prominent features of the recently characterized 5-HT4 receptor. Although pharmacologic similarities have been suggested between 5-HT-M and 5-HT4 receptors (some potent 5-HT3 antagonists are active, with lower potency, at 5-HT4 receptors), it is clear that 5-HT4 receptors are different from 5-HT-M receptors.
Hoyer
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Preclinical Research, Sandoz Pharma Ltd., Basel, Switzerland.
D000818:Animals; D006801:Humans; D011985:Receptors, Serotonin / Q000145:classification*; D009626:Terminology as Topic
D011985:Receptors, Serotonin