title: Cyclooxygenase inhibitors depress norepinephrine constriction of rat abdominal, but not thoracic, aorta.
abstract: Experiments were done on aortic rings (thoracic and abdominal) from young and retired breeder Lewis and Sprague-Dawley male rats. Constriction responses to norepinephrine, 5-hydroxytryptamine (5-HT), and prostaglandin F2 alpha, were done +/- the cyclooxygenase blockers, indomethacin or mefenamic acid. Indomethacin significantly depressed norepinephrine constriction in abdominal (but not thoracic) aorta of all groups. In additional studies of abdominal aorta from Lewis retired breeders, indomethacin and mefenamic acid depressed norepinephrine (but not 5-HT or prostaglandin F2 alpha) construction. Furthermore, indomethacin depressed norepinephrine constriction in vessels denuded of endothelial cells. The thromboxane receptor antagonist SQ 29548 did not alter norepinephrine constriction. Thus, in rat abdominal aorta, norepinephrine constriction is mediated by a constrictor prostanoid of vascular smooth muscle origin that is not thromboxane A2.
authors.affiliation: Department of Physiology, Michigan State University, East Lansing 48824-1101.
authors.forename: V L
authors.initials: VL
authors.lastname: Lamb
authors.forename: A J
authors.initials: AJ
authors.lastname: Schwartz
authors.forename: W R
authors.initials: WR
authors.lastname: Rohn
authors.forename: L
authors.initials: L
authors.lastname: Kaiser
mesh_terms: D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000375:Aging / Q000502:physiology; D000818:Animals; D001012:Aorta, Abdominal / Q000187:drug effects*; D001013:Aorta, Thoracic / Q000187:drug effects*; D019086:Bridged Bicyclo Compounds, Heterocyclic; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology*; D015237:Dinoprost / Q000494:pharmacology; D004730:Endothelium, Vascular / Q000187:drug effects / Q000502:physiology; D005231:Fatty Acids, Unsaturated; D006834:Hydrazines / Q000494:pharmacology; D066298:In Vitro Techniques; D007213:Indomethacin / Q000494:pharmacology; D008297:Male; D008528:Mefenamic Acid / Q000494:pharmacology; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D009638:Norepinephrine / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D051381:Rats; D011917:Rats, Inbred Lew; D017207:Rats, Sprague-Dawley; D017482:Receptors, Thromboxane / Q000037:antagonists & inhibitors; D012701:Serotonin / Q000494:pharmacology; D013045:Species Specificity
chemical_list: D000317:Adrenergic alpha-Antagonists; D000319:Adrenergic beta-Antagonists; D019086:Bridged Bicyclo Compounds, Heterocyclic; D016861:Cyclooxygenase Inhibitors; D005231:Fatty Acids, Unsaturated; D006834:Hydrazines; D017482:Receptors, Thromboxane; D012701:Serotonin; D008528:Mefenamic Acid; C045749:SQ 29548; D015237:Dinoprost; D009638:Norepinephrine; D007213:Indomethacin