EFFECTS OF POTASSIUM-IODIDE, COLCHICINE AND DAPSONE ON THE GENERATION OF POLYMORPHONUCLEAR LEUKOCYTE-DERIVED OXYGEN INTERMEDIATES

The effects of KI, colchicine and dapsone on the in vitro generation of [human] polymorphonuclear leukocyte (PMN)-derived O2 intermediates were investigated. These 3 drugs have beneficial effects on those conditions in which PMN play an important pathogenetic role. Three O2 intermediates, superoxide anion (O2-), H2O2, hydroxyl radical (OH.cntdot.) and chemiluminescence were included in assay studies. Dose-response studies were performed with therapeutic doses of the drugs (10 .mu.m to 1 mM). Both KI and dapsone significantly suppressed the generation of O2 intermediates, except for O2-. Colchicine decreased OH.cntdot. production. Apparently these agents to some extent exert their anti-inflammatory effects by interfering with the PMN-dependent production of O2 intermediates, conferring protection from auto-oxidative tissue injury. This may account for their clinical efficacy in many PMN-mediated dermatological diseases.