[Inhibitory effects of AA-2414, a thromboxane (Tx) A2 receptor antagonist, on U-46619-, prostaglandin (PG) D2- and 9 alpha, 11 beta PGF2-induced contractions of guinea pig tracheas and isolated human bronchi]

Abstract

The effects of a novel TXA2 receptor antagonist, AA-2414 [(+-)-7-(3,5,6-trimethyl-1,4-benzoquinone-2-yl)-7-phenyl-heptanoic acid], on U-46619-, PGD2- and 9 alpha, 11 beta-PGF2 alpha-induced contractions of isolated guinea pig tracheas and human bronchi were investigated. AA-2414 competitively inhibited the contractile responses of both human and guinea pig preparations induced by U-46619 with similar pA2 values (7.7 and 7.6, respectively). In addition, the compound also inhibited the contractions of both preparations caused by PGD2 and 9 alpha, 11 beta-PGF2 alpha, the IC50 values of which were 1.2 x 10(-7) and 1.8 x 10(-7) M in guinea pig tracheas and 2.8 x 10(-8) and 8.5 x 10(-8) M in human bronchi. These results suggest that AA-2414 may be a therapeutically useful drug for bronchial asthma.