Diphenyldisulfide inhibits indomethacin-induced ulcerogenesis in rats

Indomethacin was administered subcutaneously to rats, 4 mg/kg/day for 4 consecutive days in order to produce erosions of the small intestine which were scored at necropsy on day 5. Orally administered phenidone (up to 250 mg/kg/day), a mixed cycloocygenase-lipoxygenase inhibitor, failed to produce intestinal erosions, but tended to exacerbate indomethacin-induced erosions. A 5-LO inhibitor, diphenyldisulfide, provided significant protection at 10-100 mg/kg when given orally to indomethacin-treated rats. Sulfasalazine, auranofin and cyproheptadine, but not cimetidine, also protected, suggesting a role for mast cell activation and leukotriene generation in indomethacin-induced ulcerogenesis.