Cutaneous Thermal Injury Increases Leukocyte Adherence in Rat Mesenteric Venules by a Reactive Oxidant‐Dependent Mechanism

Abstract

Background The inflammatory response following major burns is known to cause remote organ dysfunction, although the underlying mechanisms are not yet known. Purpose: Our goal was to determine if thermal injury to the skin of rats would promote microvascular inflammation in the mesenteric microcirculation, and if the mechanism involved generation of reactive oxidants. Methods Intravital microscopy was used to assess mast cell degranulation and leukocyte adherence in mesenteric venules of anesthetized rats. Thermal injury was induced by exposing skin on the back of animals to steam for 30 sec or 1 min. The area of injury was ~ 20 or 40% of the total body surface area. Control animals were not exposed to steam. Results: Leukocyte adherence significantly increased during 5 h after burn, but not in control animals. Mast cell degranulation was not increased by burns, and the antioxidant lipoic acid significantly attenuated leukocyte adherence in burned rats. Conclusions Thermal injury to the skin of rats resulted in microvascular inflammation in the mesenteric microcirculation of rats by a mechanism dependent on generation of reactive oxidants.