Premium
Differential release of eicosanoids by bradykinin, arachidonic acid and calcium ionophore A23187 in guinea‐pig isolated perfused lung
Author(s) -
Bakhle Y.S.,
Moncada S.,
Nucci G.,
Salmon J.A.
Publication year - 1985
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.1476-5381.1985.tb09434.x
Subject(s) - arachidonic acid , ionophore , leukotriene , bradykinin , leukotriene c4 , chemistry , guinea pig , eicosanoid , endocrinology , medicine , thromboxane , calcium , prostaglandin , thromboxane b2 , radioimmunoassay , prostaglandin e , biochemistry , biology , receptor , enzyme , platelet , asthma , organic chemistry
1 The effects of infusions of bradykinin (0.2 μM), calcium ionophore A23187 (0.5 μM) and arachidonic acid (13 μM) on the release of eicosanoids from the guinea‐pig isolated perfused lung were investigated using radioimmunoassay for thromboxane B 2 (TXB 2 ), 6‐oxo‐prostaglandin F 1α (6‐oxo‐PGF 1α ), PGE 2 , leukotriene B 4 (LTB 4 ) and LTC 4 and bioassay using the superfusion cascade. 2 Bradykinin released more 6‐oxo‐PGF 1α than TXB 2 , whereas arachidonic acid and ionophore released more TXB 2 than 6‐oxo‐PGF 1α . 3 The time course of eicosanoid release varied with the stimulus: bradykinin and arachidonic acid produced an immediate release, whereas the ionophore showed a slower onset of release. 4 Although the amounts of LTB 4 and LTC 4 released by the ionophore were very low according to radioimmunoassays, there was evidence from the bioassay of release of a leukotriene‐like substance, thought to be LTD 4 . 5 The leukotriene antagonist FPL 55712 lacks specificity in the guinea‐pig trachea; at the concentration used (2 μM) it antagonized contractions of the tracheal strip to PGE 2 as well as to LTC 4 . 6 Our results show that in the guinea‐pig perfused lung the metabolism of exogenous arachidonic acid is both qualitatively and quantitatively different from the metabolism of endogenous arachidonic acid; furthermore, the profile of eicosanoid production is stimulus‐dependent.