Reactivity of the bronchial artery to 5-hydroxytryptamine.
The activity of 5-hydroxytryptamine and its antagonism by the selective 5-HT2 serotonergic receptor antagonist, ketanserin, was tested on the bronchial arteries of three domestic species; bovine, equine and ovine. 5-hydroxytryptamine contracted the bronchial artery in the bovine (threshold: 1.0 X 10(-9) M), the equine (threshold: 1.0 X 10(-9) M) and ovine (threshold: 5.0 X 10(-9) M), dose-dependently. Ketanserin on the bronchial artery of the bovine (concentrations: 1.0 X 10(-9) M and 1.0 X 10(-8) M), equine (concentrations: 1.0 X 10(-10) M, 1.0 X 10(-9) M and 1.0 X 10(-8) M) and ovine (concentrations: 1.0 X 10(-10) M, 5.0 X 10(-10) M and 1.0 X 10(-9) M), significantly (p less than 0.05) shifted the concentration response curves to 5-hydroxytryptamine and caused a depression of the maximum at the higher concentrations. The data indicates the presence of 5-HT2 serotonergic receptors in the bronchial artery of these species. The depression may possibly be due to the antagonist's adrenolytic properties.
D000818:Animals; D001981:Bronchial Arteries / Q000187:drug effects*; D002417:Cattle; D005260:Female; D006736:Horses; D066298:In Vitro Techniques; D007650:Ketanserin; D008297:Male; D010880:Piperidines / Q000494:pharmacology; D011985:Receptors, Serotonin / Q000187:drug effects*; D012701:Serotonin / Q000494:pharmacology*; D012702:Serotonin Antagonists / Q000494:pharmacology; D012756:Sheep; D014661:Vasoconstriction / Q000187:drug effects
D010880:Piperidines; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; D012701:Serotonin; D007650:Ketanserin