[Effect of acetylcholine on contractile reactions of the cat ileum induced by serotonin before and after cholinoreceptor blockade].
In acute experiments on cats, an isolated portion of the ileum was vascularly perfused. Contractile activity of the ileum was estimated by isometric tension. The subthreshold dose of acetylcholine (6.10(-10) mol/ml, 1 ml/min) facilitated the contractile responses of the ileum induced by i.a. administration of serotonin (2.5 . 10(-8) or 5 . 10(-8) mol). Blockade of nicotinic receptors with benzohexonium (10 mg/kg) diminished the serotonin-induced contractile responses but did not affect the facilitating effect of acetylcholine. Blockade of muscarinic receptors with atropine (0.2 ml/kg) abolished the serotonin-induced responses. The facilitating effect of acetylcholine on the serotonin-induced contractile responses of the ileum seems to be actualized at postganglionic level of the intramural nervous plexus with the participation of muscarinic cholinoreceptors.
D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D001285:Atropine / Q000008:administration & dosage; D002415:Cats; D004347:Drug Interactions; D005769:Gastrointestinal Motility / Q000187:drug effects*; D006584:Hexamethonium Compounds / Q000008:administration & dosage; D007082:Ileum / Q000294:innervation; D009130:Muscle, Smooth / Q000187:drug effects; D011950:Receptors, Cholinergic / Q000502:physiology*; D011976:Receptors, Muscarinic / Q000502:physiology; D011978:Receptors, Nicotinic / Q000502:physiology
D006584:Hexamethonium Compounds; D011950:Receptors, Cholinergic; D011976:Receptors, Muscarinic; D011978:Receptors, Nicotinic; D001285:Atropine; D000109:Acetylcholine; C021628:benzohexonium
Vliianie atsetilkholina na sokratitel'nye reaktsii podvzoshnoĭ kishki koshki, vyzvannye serotoninom, do i posle blokady kholinoretseptorov.