title: Pharmacological analysis of vasoconstrictor responses to ATP of isolated, perfused dog mesenteric arteries.
abstract: The stainless steel cannula inserting method was used to analyze the characteristics of the vasoconstriction induced by ATP in isolated, perfused dog mesenteric arteries. A dose of 100-1000 micrograms of ATP induced vasoconstriction. It was produced repetitively at 20-min intervals. The vasoconstriction was not modified by phentolamine in doses which completely inhibited norepinephrine-induced vasoconstriction. Aminophylline significantly suppressed ATP-induced vasoconstrictions. KCl-induced vasoconstriction was significantly depressed by a potent Ca antagonist, diltiazem. ATP-induced vasoconstriction was also significantly suppressed by diltiazem but to a lesser degree. ATP-induced vasoconstriction was not significantly suppressed by 30 and 100 micrograms of dipyridamole. After treatment with intraluminal saponin (0.3-3 mg) which caused a disappearance of the vascular endothelium, the ATP-induced vasoconstrictor response was significantly enhanced. From these results it is concluded that ATP-induced vasoconstriction may be mediated via P1-purinoceptors and be partially due to increases in activation of Ca inward current.
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology*; D000628:Aminophylline / Q000494:pharmacology; D000818:Animals; D004110:Diltiazem / Q000494:pharmacology; D004176:Dipyridamole / Q000494:pharmacology; D004285:Dogs; D005260:Female; D066298:In Vitro Techniques; D008297:Male; D008638:Mesenteric Arteries / Q000187:drug effects* / Q000502:physiology; D009638:Norepinephrine / Q000494:pharmacology; D010646:Phentolamine / Q000494:pharmacology; D011189:Potassium Chloride / Q000494:pharmacology; D012503:Saponins / Q000494:pharmacology; D014661:Vasoconstriction / Q000187:drug effects*; D014662:Vasoconstrictor Agents / Q000494:pharmacology*
chemical_list: D012503:Saponins; D014662:Vasoconstrictor Agents; D000628:Aminophylline; D004176:Dipyridamole; D011189:Potassium Chloride; D000255:Adenosine Triphosphate; D004110:Diltiazem; D009638:Norepinephrine; D010646:Phentolamine