Muscarinic Acetylcholine Receptor M1-M5 Subtypes (mAChR M1-M5)

Muscarinic acetylcholine receptors (mAChRs) are a family of five G protein-coupled receptor subtypes (M1-M5) that mediate the effects of acetylcholine in the central and peripheral nervous systems. They play critical roles in cognition, heart rate regulation, smooth muscle contraction, glandular secretion, and modulation of neurotransmitter release. Each subtype is encoded by a distinct gene and couples to different G proteins (Gq/11 or Gi/o), leading to activation of phospholipase C or inhibition of adenylyl cyclase, respectively. They represent important therapeutic targets across neurology, psychiatry, cardiology, ophthalmology, and drug addiction, and ongoing advances continue to refine our ability to selectively modulate their activity using structure-based drug design approaches.

Other names

M1 receptorM2 receptorM3 receptorM4 receptorM5 receptorCHRM1CHRM2CHRM3CHRM4CHRM5

Agonism or antagonism of muscarinic acetylcholine receptors, leading to downstream effects via G protein signaling pathways (Gq/11 activation of phospholipase C or Gi/o inhibition of adenylyl cyclase).