title: Sympathetic-dependence in bradykinin-induced synovial plasma extravasation is dose-related.
abstract: While previous studies have implicated a role for sympathetic postganglionic neuron-terminals in bradykinin-induced plasma extravasation, a recent report by Cambridge and Brain [Br. J. Pharmacol., 115 (1995) 641-647] has suggested that it is sympathetic-independent. However, the doses of bradykinin used in these two groups of studies were considerably different. Therefore, in the present study, we characterized the sympathetic-dependence of plasma extravasation at varying doses of bradykinin. By measuring the concentration of Evans blue dye extravasation into the joint perfusate following its intravenous injection, bradykinin-induced plasma extravasation in the knee joint cavity was determined spectrophotometrically. To examine the role of sympathetic postganglionic neuron terminals in mediating bradykinin-induced plasma extravasation, we used surgical ablation of the lumbar sympathetic chain. Intra-articular perfusion of BK dose-dependently increased synovial plasma extravasation. After surgical sympathectomy, the dose-response curve for bradykinin-induced plasma extravasation was significantly shifted to the right. We conclude that at concentrations observed in inflamed tissues (between 10(-8) and 10(-7) M), bradykinin-induced plasma extravasation is largely mediated by sympathetic postganglionic neuron terminals.
authors.affiliation: Department of Medicine, University of California at San Francisco 94143-0452, USA.
authors.forename: F J
authors.initials: FJ
authors.lastname: Miao
authors.forename: P G
authors.initials: PG
authors.lastname: Green
authors.forename: T J
authors.initials: TJ
authors.lastname: Coderre
authors.forename: W
authors.initials: W
authors.lastname: Jänig
authors.forename: J D
authors.initials: JD
authors.lastname: Levine
mesh_terms: D000818:Animals; D001920:Bradykinin / Q000494:pharmacology*; D004396:Coloring Agents / Q000493:pharmacokinetics; D004305:Dose-Response Relationship, Drug; D005070:Evans Blue / Q000493:pharmacokinetics; D005119:Extravasation of Diagnostic and Therapeutic Materials / Q000378:metabolism; D007719:Knee Joint / Q000276:immunology / Q000378:metabolism / Q000503:physiopathology; D008297:Male; D010949:Plasma / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D017779:Sympathetic Fibers, Postganglionic / Q000187:drug effects* / Q000378:metabolism; D013582:Synovial Fluid / Q000187:drug effects* / Q000378:metabolism; D013585:Synovitis / Q000378:metabolism
chemical_list: D004396:Coloring Agents; D005070:Evans Blue; D001920:Bradykinin