This is one of the several different receptors for 5-hydroxytryptamine (serotonin). 5-HT plays important roles in various behavioral and physiological processes in aplysia. These include feeding, locomotion, circadian rhythm, learning and memory, synaptic plasticity, and synaptic growth. This receptor is mediated by G proteins that stimulate phospholipase C. Reproductive system. Belongs to the G-protein coupled receptor 1 family.