alfa2C

alfa2C, commonly referring to the alpha-2C adrenergic receptor, is a member of the α2-adrenergic receptor family. In humans it is typically designated α2C-AR and is encoded by the ADRA2C gene. It is a G protein-coupled receptor that responds to catecholamines such as norepinephrine and epinephrine.

Structurally, α2C-AR shares the seven-transmembrane domain architecture typical of GPCRs. Upon activation it couples primarily to Gi/o proteins, leading to inhibition of adenylyl cyclase, reduced cyclic AMP levels, and modulation of ion channels that can decrease neuronal excitability and neurotransmitter release. This signaling contributes to the receptor’s roles in regulating peripheral vascular tone and central nervous system processes.

Expression studies show that α2C-AR is enriched in the central nervous system, including regions such as the striatum and other limbic structures, where it modulates neurotransmission, sleep, mood, and stress responses. It is also present in various peripheral tissues, where it participates in vascular and metabolic regulation, often in concert with other α2-adrenergic receptor subtypes (α2A and α2B).

Genetic variation in ADRA2C includes polymorphisms such as a deletion variant described in some populations, which can alter receptor signaling or interaction with other adrenergic receptors. Associations with stress responsiveness, cardiovascular regulation, and responses to adrenergic drugs have been investigated, but findings are not wholly consistent across studies.

In research and clinical contexts, α2C-AR contributes to the overall physiological and pharmacological effects of α2-adrenergic signaling. While no drug specifically targets α2C in a highly selective way, the receptor participates in the effects of adrenergic agonists and antagonists that influence sedation, analgesia, and autonomic regulation.