Actions of the novel bronchodilator, trimetaquinol, on bovine pulmonary vein.
The actions of the beta-sympathomimetic bronchodilator trimetaquinol (TMQ) were examined on bovine pulmonary vein smooth muscle in vitro. TMQ partially and reversibly inhibited 5-hydroxytryptamine (5HT) induced contractions of the vein strips. The relaxant activity was neither blocked by propranolol (10(-7) M) nor enhanced by phentolamine (10(-7) M). Isoproterenol, alone or in the presence of phentolamine (10(-7) M), was much less effective than TMQ in relaxing 5HT-induced contractions. From these results it is suggested that TMQ functions via a "non-beta-adrenergic" mechanism to relax bovine pulmonary vein smooth muscle.
D000818:Animals; D002417:Cattle; D006633:Histamine Antagonists; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology; D007546:Isoquinolines / Q000494:pharmacology*; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects; D011667:Pulmonary Veins / Q000187:drug effects*; D012701:Serotonin / Q000494:pharmacology; D012702:Serotonin Antagonists; D014213:Tretoquinol / Q000494:pharmacology*
D006633:Histamine Antagonists; D007546:Isoquinolines; D012702:Serotonin Antagonists; D012701:Serotonin; D014213:Tretoquinol; D007545:Isoproterenol