title: [The mode of action of bisacodyl on the smooth muscle of the small and the large intestine of the guinea pig].
abstract: 4,4'-Diacetoxy-diphenyl-(pyridyl-2)-methan (Bisacodyl, Dulcolax, 12--240 mug/ml) was shown to initiate dose-dependently contracile responses in the guinea pig isolated terminal ileum and taenia coli (a preparation of pure longitudinal muscle fibers). In contrast to muscle contractions induced by 1 mug/ml acetylcholine (ACh) and 1 mug/ml histamine, respectively bis-acodyl-induced contractile responses were antagonized neither by the anticholinergic agent atropine (6 mug/ml) nor by the antihistaminic compound pheniramine (6 mug/ml). On the other hand, bisacodyl inhibited contractile responses induced by ACh or histamine in a dose-dependent manner. The possibility that bisacodyl-induced contractions were due to a fall in cyclic 3,5-AMP level was excluded by estimation of endogenous cyclo-AMP. Since exogenous cyclic 3,5-AMP (which should possess calcium-antagonistic properties in smooth muscle) as well as verapamil (a calcium inhibitor) inhibited bisacodyl-induced contractions, a site of action on the calcium-dependent contractile system of the smooth muscle cell was discussed. Furthermore, bisacodyl should diminish the sensibility of the contractile system to other contractile compounds (ACh, histamine).
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001285:Atropine / Q000494:pharmacology; D001726:Bisacodyl / Q000008:administration & dosage / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D002118:Calcium / Q000494:pharmacology; D003106:Colon / Q000187:drug effects; D003408:Cresols / Q000494:pharmacology*; D000242:Cyclic AMP / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005260:Female; D006168:Guinea Pigs; D006632:Histamine / Q000494:pharmacology; D007082:Ileum / Q000187:drug effects; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects*; D010528:Peristalsis / Q000187:drug effects; D010632:Pheniramine / Q000494:pharmacology; D014700:Verapamil / Q000494:pharmacology
chemical_list: D003408:Cresols; D001726:Bisacodyl; D010632:Pheniramine; D001285:Atropine; D006632:Histamine; D014700:Verapamil; D000242:Cyclic AMP; D000109:Acetylcholine; D002118:Calcium
vernacular_title: Zur Wirkungsweise von Bisacodyl auf die glatte Muskulatur des Dünn- und Dickdarms vom Meerschweinchen