Serotonin 5-hydroxytryptamine type 4 receptor (5-HT4)

The serotonin 5-hydroxytryptamine type 4 receptor (5-HT4) is a G protein-coupled receptor (GPCR) that binds the neurotransmitter serotonin (5-hydroxytryptamine, 5-HT). It is encoded by the HTR4 gene. The primary signaling pathway involves coupling to Gαs proteins, which stimulates adenylate cyclase activity and increases intracellular cAMP levels, leading to activation of protein kinase A (PKA). It's expressed in the CNS and peripheral organs. Activation of this receptor has been shown to boost dendritic spine formation/function, important for synaptic plasticity, and modulate behaviors related to feeding and addiction. Agonists are used to treat gastrointestinal conditions.

Other names

HTR45-hydroxytryptamine receptor 4

Agonists stimulate adenylate cyclase activity, increasing intracellular cAMP levels and activating protein kinase A (PKA). Also activates Src and ERK kinases independently of G-proteins to a certain extent.