EFFECTS OF ALLOPURINOL, IBUPROFEN AND CYCLOSPORINE-A ON LOCAL MICROCIRCULATORY DISTURBANCES DUE TO BURN INJURIES

This experiment was designed to study the reactions in the surrounding area of burn injury that may lead to further necrosis in 24 h. To pre vent extension of burn size into the tissue adjacent to burn injury, i t was attempted to reduce progressive microvascular damage by differen t drugs (ibuprofen, allopurinol or cyclosporin A (CyA)) in a rat model . The burn model consisted of a row of four 10x20 mm burn areas separa ted by three unburned 5x20mm skin bridges (interspaces). To evaluate m icrocirculation and perfusion of panniculus carnosus muscle which is b eneath the burned area of skin, the radioactive agent, technetium-99m methoxyisobutylisonitrile (Tc-99(m)-MIBI) was used 24 h after the burn . Capillary permeability of injured tissue was assessed by the wet and dry weight technique. In all study groups, interspaces showed higher uptakes of Tc-99(m)-MIBI between 40 and 95 per cent, in comparison wit h burn sites in the first 24 h following burn. Among the treated rats better results were obtained by allopurinol and CyA treatment that com menced before burn than ibuprofen. Wet and dry ratios were found to be significantly lower in interspaces in rats pretreated with allopurino l and CyA. Results of this experiment showed that neutrophils and free radical-mediated injury may be involved in the pathogenesis of local response to thermal injury, and allopurinol and CyA have some effects to prevent progressive ischaemia, capillary compromise and oedema. (C) 1997 Elsevier Science Ltd for ISBI.