The Role of Histamine and Serotonin in the Inflammatory Reaction in an Experimental Model of Open Wounds in the Rat

Abstract

The role of histamine and serotonin in the inflammatory reaction in the granulation tissue of open wounds in the rat was studied. The model involved plastic chambers attached to the edges of two open circular full-thickness skin wounds. Five days post-wounding, agonists or antagonists were applied in one of the two chambers, the adjacent wound serving as control. Thereafter blood flow and albumin extravasation were measured. Application of histamine (100 µM) caused an increase in granulation tissue blood flow by 36%, but left albumin extravasation unaffected. Treatment with mepyramine (H₁ antagonist, 20 µM), cimetidine (H₂ antagonist, 20 µM) or methysergide (serotonin antagonist, 20 µM) did not influence the level of either blood flow or albumin extravasation. It is suggested that endogeneous histamine and serotonin play a minor role in the inflammatory process in the granulation tissue of this model of healing wounds.