Progressive tissue injury in burns is reduced by rNAPc2.

Abstract

Burn wounds are characterised by central necrosis surrounded by an area of stasis with compromised perfusion. Secondary aggravation of the burn wound due to ischaemia in the zone of stasis can also result in necrosis. This study aims to improve circulation in the zone of stasis by reducing microthrombus formation and thereby to reduce secondary aggravation. Recombinant nematode anticoagulant protein (rNAPc2) was administered to Wistar rats at 3 or 30 microg/kg as a single or daily dose. A comb pattern burn was induced on the dorsum of these rats and its evolution monitored by serial photography, planimetry, laser doppler flowmetry and immunohistochemistry. In the 30 microg/kg daily group, extension of the burn wound was curbed, limiting the burn area to 1.99+/-0.67 cm(2) on day 28, compared to 3.51+/-0.37 cm(2) in the control group (p=0.015). Laser doppler evaluation showed a significant (p<0.001) increase in circulation in the first day post-burn. Significantly less (p<0.001) microvascular fibrin formation was observed by immunohistochemistry. Anticoagulation with rNAPc2 improved perfusion of the burn wound. The resultant reduction in the area of the burn led to earlier healing and less scar contracture.