Comparison of Muscarinic receptor types－快樂小藥師 Im pharmacist nichts glücklich

Comparison of Muscarinic receptor types

Type	Gene	Function	PTX	CTX	Effectors	Agonists	Antagonists
M₁	CHRM1	EPSP in autonomic ganglia secretion from salivary glands and stomach In CNS (memory?)	no (yes)	no (yes)	G_q (G_i) (G_s): Slow EPSP. ↓ K⁺ conductance	acetylcholine oxotremorine carbachol McNA343	atropine dicycloverine tolterodine oxybutynin ipratropium mamba toxin MT7 pirenzepine telenzepine
M₂	CHRM2	slow heart rate reduce contractile forces of atrium reduce conduction velocity of AV node In CNS homotropic inhibition	yes	no	G_i ↑ K⁺ conductance ↓ Ca²⁺ conductance	acetylcholine methacholine carbachol oxotremorine	atropine dicycloverine tolterodine oxybutynin ipratropium methoctramine tripitamine gallamine Himbacine
M₃	CHRM3	smooth muscle contraction increased endocrine and exocrine gland secretions, e.g. salivary glands and stomach In CNS Eye accommodation vasodilation induce emesis	no	no	G_q	acetylcholine bethanechol carbachol oxotremorine pilocarpine (in eye)	atropine dicycloverine tolterodine oxybutynin ipratropium darifenacin tiotropium
M₄	CHRM4	Enhanced locomotion In CNS	yes	?	G_i ↑ K⁺ conductance ↓ Ca²⁺ conductance	acetylcholine carbachol oxotremorine	atropine dicycloverine tolterodine oxybutynin ipratropium mamba toxin MT3
M₅	CHRM5	In CNS	no	?	G_q	acetylcholine carbachol oxotremorine	atropine dicycloverine tolterodine oxybutynin ipratropium