COMPARATIVE EFFECTIVENESS AND MOLECULAR PHARMACOLOGICAL MECHANISMS OFANTIALLERGIC AGENTS ON EXPERIMENTAL CONJUNCTIVITIS IN MICE

The purpose of this study was to determine the effectiveness of antial lergic agents in the treatment of experimental murine ragweed conjunct ivitis. SWR/J mice were divided into eight groups: 1; normal controls (unmanipulated); 2, untreated; 3, lodoxamide; 4, cromolyn; 5, livocarb astine; 6, nedocromil; 7, buffer solution (BS); and 8, tetrandine (TDR ). Groups 2-8 were exposed to ragweed pollen through topical applicati on to conjunctival and nasal mucosa, followed by conjunctival challeng e with the allergen. Allergic conjunctivitis was evaluated by scoring of the clinical signs and histopathology. mRNA gene expression of inte rleukin 1 beta (IL-1 beta), IL-6 and tumor necrosis factor alpha (TNF- alpha) in conjunctiva was analyzed by reverse transcription polymerase chain reaction techniques. Exposed mice developed allergic conjunctiv itis clinically and histologically that was modulated by topical lodox amide, cromolyn, livocarbastine, or nedocromil eye drops or TDR intrap eritoneally injected. Histopathologic analysis demonstrated that the d rugs and TDR significantly reduced conjunctival eosinophil infiltratio n and the number of intact and degranulating mast cells. IL-1 beta and TNF-alpha mRNA gene expression in conjunctiva of treated mice was inh ibited compared with untreated and BS-treated controls. No IL-6 mRNA e xpression was observed even on the conjunctiva of the untreated mice. The antiallergic drugs and TDR exerted a similar action on the murine model of allergic conjunctivitis and demonstrated pharmacologic effect iveness on the conjunctival mRNA expression of cytokines IL-1 beta and TNF-alpha.