COLLAGENASE DURING BURN WOUND-HEALING - INFLUENCE OF A HYDROGEL DRESSING AND PULSED ELECTRICAL-STIMULATION

Epithelialization of second-degree burn wounds is known to be accelera ted by topical treatment with hydrogel dressings and further enhanced by pulsed electrical stimulation compared with no treatment (air expos ure). Tissue collagenase has been proposed to be involved during the p rocess of epithelialization. In the present study collagenase levels w ere examined in partial-thickness burn wounds in the skin of four dome stic pigs. Collagenase levels, assayed on postburn days 1 to 10, were substantially reduced in deblistered and air-exposed burn wounds compa red with excisional partial-thickness wounds. Early application of hyd rogel dressing to the burn wounds was accompanied by elevated collagen ase activities and an increased inflammatory reaction in dermis. Addit ion of pulsed electrical stimulation increased (p < 0.001) collagenase levels twofold above those with hydrogel alone during initiation of e pithelialization (postburn days 3 and 4). These results suggest that c ollagenase is closely linked to wound epithelialization.