Acetylcholine and "auto-inhibition".
D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D001949:Bretylium Compounds / Q000494:pharmacology; D004558:Electric Stimulation; D006321:Heart / Q000187:drug effects; D006584:Hexamethonium Compounds / Q000494:pharmacology; D007082:Ileum / Q000187:drug effects; D066298:In Vitro Techniques; D008638:Mesenteric Arteries / Q000187:drug effects; D009638:Norepinephrine / Q000378:metabolism*; D010393:Pempidine / Q000494:pharmacology; D011817:Rabbits; D051381:Rats; D011950:Receptors, Cholinergic; D011955:Receptors, Drug; D013564:Sympathetic Nervous System / Q000502:physiology*
D001949:Bretylium Compounds; D006584:Hexamethonium Compounds; D011950:Receptors, Cholinergic; D011955:Receptors, Drug; D010393:Pempidine; D000109:Acetylcholine; D009638:Norepinephrine