EFFECT OF LODOXAMIDE ON INVITRO AND INVIVO CONJUNCTIVAL IMMEDIATE HYPERSENSITIVITY RESPONSES IN RATS

The antiallergic compound, lodoxamide, was evaluated for its abilities to attenuate a local allergic reaction in rat conjunctiva in vivo and to inhibit rat conjunctival mast cell mediator release in vitro. Topi cally applied lodoxamide (0.01, 0.10 and 1.0%, w/v) dose-dependently r educed the allergic response (23, 43 and 72%, respectively) in vivo. L odoxamide was more effective than cromolyn sodium, N-acetyl aspartyl g lutamic acid (Naaxia(R)) and levocabastine, and 25 (7-200) times more potent than nedocromil sodium in direct comparisons. Addition of lodox amide (10 mug/ml) to sensitized conjunctival tissue in vitro immediate ly prior to antigen challenge significantly reduced the amount of hist amine released by the tissue. These data suggest that lodoxamide's in vivo antiallergic activity in the conjunctiva is associated with its a bility to prevent allergic mediator release from mast cells contained in this same tissue.