Luminal responses to bradykinin on the isolated canine tracheal epithelium: effects of bradykinin antagonists.
We have tested the ability of several B2 antagonists on the responses of the open-circuited isolated canine tracheal epithelium to the luminal addition of Bradykinin (BK), Lys-BK, and substance P (SP). All three peptides produced biphasic changes in transmural potential difference (PD), an initial decrease (dip) followed by an increase (rise). The B2 antagonists D-Arg0 [Hyp3,Thi5,8,D-Phe7]BK (B5630) reversibly inhibited both the dips and the rise with IC50 values of 2.01 x 10(-8) and 1.54 x 10(-7) M, respectively. The responses to SP were unaffected even with high concentrations of the antagonist. Other antagonists tested [D-Phe1,7,Thi5,8]BK (B4158), [D-Phe2,7]BK (B4404), and [D-Phe7,Hyp8]BK (B5092) were ineffective.
Rangachari
P K
PK
Department of Medicine, McMaster University, Hamilton, Ontario, Canada.
Donoff
B
B
Vavrek
R J
RJ
Stewart
J M
JM
D000595:Amino Acid Sequence; D000818:Animals; D001920:Bradykinin / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000494:pharmacology*; D004285:Dogs; D004848:Epithelium / Q000187:drug effects / Q000502:physiology; D066298:In Vitro Techniques; D007609:Kallidin / Q000494:pharmacology; D008564:Membrane Potentials / Q000187:drug effects; D008969:Molecular Sequence Data; D018002:Receptors, Bradykinin; D017981:Receptors, Neurotransmitter / Q000187:drug effects / Q000502:physiology; D014132:Trachea / Q000187:drug effects* / Q000502:physiology
D018002:Receptors, Bradykinin; D017981:Receptors, Neurotransmitter; D007609:Kallidin; D001920:Bradykinin