Pharmacological characterization of mouse ear PCA.

Effects of some antiallergic agents on homologous passive cutaneous anaphylaxis (PCA) in mouse ear were investigated by means of assessing the amount of extravasated dye. Antihistamines (chlorpheniramine and diphenhydramine) and antiserotonins (methysergide and cyproheptadine) suppressed mouse ear PCA significantly. In contrast, an antagonist of slow reacting substance of anaphylaxis (SRS-A) (FPL 55712) and an inhibitor of SRS-A synthesis (AA-861) did not suppress the reaction. beta-Adrenergic stimulants (isoproterenol and salbutamol) and theophylline, which elevate cyclic AMP (cAMP) levels, also suppressed mouse ear PCA significantly. The antiallergic agents, N(3',4'-dimethoxycinnamoyl)anthranilic acid(N-5') and ketotifen suppressed mouse ear PCA significantly, but disodium cromoglycate (DSCG) failed to suppress the reaction.