title: Luminal receptors for bradykinin on the canine tracheal epithelium: functional subtyping.
abstract: Luminal addition of bradykinin (BK) to the open-circuited canine tracheal epithelium produces a biphasic response in transmucosal potential difference (P.D.): a rapid, transient decrease (dip) followed by a subsequent, more sustained increase (rise), both phases being associated with an increase in conductance. We have attempted to characterise the receptor subtype mediating the bradykinin response. Lys-bradykinin (Lys-BK) elicited a similar response, and its EC50 as judged from concentration-response relations was similar to that of BK. Cross-tachyphylaxis between the two peptides confirmed a common receptor. Des-Arg9-BK (a B1-agonist) neither elicited a response nor inhibited responses to BK. The novel B2-antagonist [Thi6,9-D-Phe8]kallidin reversibly inhibited responses to both BK and Lys-BK. The rapid changes in P.D. (dips) were unaffected by Na+ removal, but were eliminated by replacing luminal Cl- with isethionate. Thus, BK, acting on B2-receptors, transiently increases anion permeability of the luminal membrane of the canine tracheal epithelium.
mesh_terms: D000818:Animals; D001920:Bradykinin / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D004285:Dogs; D004848:Epithelium / Q000032:analysis; D066298:In Vitro Techniques; D007477:Ions; D008564:Membrane Potentials / Q000187:drug effects; D018002:Receptors, Bradykinin; D017981:Receptors, Neurotransmitter / Q000032:analysis* / Q000187:drug effects; D013618:Tachyphylaxis; D014132:Trachea / Q000032:analysis* / Q000187:drug effects
chemical_list: D007477:Ions; D018002:Receptors, Bradykinin; D017981:Receptors, Neurotransmitter; D001920:Bradykinin