5-Hydroxytryptamine Receptor 6
Up to date, there are 14 different subtypes of 5-HT receptors (5-HTR) discovered and they are divided into seven major classes (5-HT1 to 5-HT7). All these receptors are G protein-coupled receptors (GPCRs), except for 5-HT3 that is a part of the Cys-loop superfamily of ligand-gated ion channels (LGICs). 5-HT1 class (composed by 5 subtypes – 5-HT1a-f) is coupled with a Gi/o protein, which inhibits adenylate cyclase (AC) activity and modulates calcium and potassium channels; 5-HT2 class (composed by 3 subtypes – 5-HT2a-c) is coupled with a Gq protein, which activates the phospholipase C pathways and releases inositol triphosphate (IP3) and diacylglycerol (DAG). The last group is composed by 5-HT4 to 5HT7 receptors and they are all Gs coupled; therefore, their activation regulates positively the function of AC (Marazziti et al. 2013).
5-HT6was first found in NCB-20 cells in 1979 by MacDermont and coworkers, but its...
Author financial support: CAPES (Coordination for the Improvement of Higher Education Personnel).
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