5-HT Receptor

5-HT receptors (5-hydroxytryptamine receptors) constitute a diverse neurotransmitter receptor family that regulates excitatory and inhibitory signaling across the central and peripheral nervous systems through G protein-coupled receptor pathways and ligand-gated ion channel mechanisms^[1][4]. The receptor family controls intracellular second-messenger signaling, including cAMP, phospholipase C, inositol trisphosphate, and calcium mobilization, thereby influencing synaptic transmission, neuronal excitability, and neuroplasticity^[1][5]. Mechanistically, most 5-HT receptor subtypes are G protein-coupled receptors, whereas 5-HT₃ receptors form cation-selective ligand-gated ion channels that mediate rapid neuronal depolarization^[1][2]. In disease-relevant models, dysregulated 5-HT receptor signaling has been associated with depression, psychosis, aggression, pain processing, and other neuropsychiatric disorders, supporting their importance as pharmacological targets^[5][3][6]. Compared with related isoforms, receptor diversity is further expanded through alternative splicing and RNA editing, particularly within 5-HT_2C, 5-HT₄, 5-HT₆, and 5-HT₇ receptors, resulting in subtype-specific signaling and pharmacological properties^[1]. For experimental applications, selective agonists and antagonists targeting 5-HT_1A, 5-HT_2A, and 5-HT₇ receptors have been widely used to investigate synaptic plasticity, antidepressant mechanisms, psychotropic responses, and receptor-mediated cAMP signaling pathways^[3][6][7].