title: Effects of aminophylline and the removal of external Na on the antispasmodic action of isoproterenol in  isolated rat rectum, particularly in relation to Ca.
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000628:Aminophylline / Q000494:pharmacology*; D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology*; D009119:Muscle Contraction / Q000187:drug effects*; D009129:Muscle Tonus / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects; D010276:Parasympatholytics / Q000494:pharmacology*; D051381:Rats; D012964:Sodium / Q000494:pharmacology*
chemical_list: D010276:Parasympatholytics; D000628:Aminophylline; D012964:Sodium; D007545:Isoproterenol; D000109:Acetylcholine; D002118:Calcium