Premium
Bradykinin B 2 receptor‐mediated phosphoinositide hydrolysis in bovine cultured tracheal smooth muscle cells
Author(s) -
Marsh Katrina A.,
Hill Stephen J.
Publication year - 1992
Publication title -
british journal of pharmacology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.432
H-Index - 211
eISSN - 1476-5381
pISSN - 0007-1188
DOI - 10.1111/j.1476-5381.1992.tb12765.x
Subject(s) - bradykinin , bradykinin receptor , agonist , medicine , endocrinology , receptor , receptor antagonist , chemistry , inositol phosphate , antagonism , inositol , antagonist , biology , biochemistry
1 Bovine tracheal smooth muscle cells were established in culture to study agonist‐induced phosphoinositide (PI) hydrolysis in this tissue. 2 Bradykinin (0.1 n m ‐10 μ m ) evoked a concentration‐dependent increase (log EC 50 ( m ) = −9.4 ±0.2; n = 8) in the accumulation of total [ 3 H]‐inositol phosphates in cultured tracheal smooth muscle cells whereas the selective B 1 receptor agonist des‐Arg 9 ‐bradykinin (10 μ m ) was significantly less effective (16% of bradykinin maximal response; relative potency = 0.2 with respect to bradykinin = 100). 3 The bradykinin‐induced increase in PI hydrolysis was unaffected by the B 1 receptor antagonist des‐Arg 9 [Leu 8 ]‐bradykinin (1 n m ‐1 μ m ) but showed marked attenuation in the presence of the B 2 receptor antagonists d ‐Arg,[Hyp 3 , d ‐Phe 7 ]‐bradykinin (10 n m ‐10 μ m ) or d ‐Arg[Hyp 3 ,Thi 5,8 , d ‐Phe 7 ]‐bradykinin (10 n m ‐10 μ m ). The estimated K B values obtained for these two compounds, assuming competitive antagonism, were 40 ± 14 n m and 8.6 ± 2.8 n m for d ‐Arg,[Hyp 3 , d ‐Phe 7 ]‐bradykinin and d ‐Arg[Hyp 3 ,Thi 5,8 , d ‐Phe 7 ]‐bradykinin respectively. 4 We conclude that bradykinin B 2 receptors are expressed in cultured bovine tracheal smooth muscle cells and are coupled to PI hydrolysis mechanisms.