The effect of prostaglandin E1 versus ischemia-reperfusion injury of musculocutaneous flaps

The purpose of this study was twofold. To evaluate whether prostaglandin E1 can increase the survival of the flap, and to determine its function again st ischemia-reperfusion injury in musculocutaneous flaps. Thirty-five Sprag ue-Dawley rats weighing 250 to 350 g were analyzed. The transverse rectus a bdominis musculocutaneous flap was used in all rats. The rats were divided into three groups: group 1 (N = 15), the control group with 4-hour ischemic injury and intraflap injection of normal saline followed by reperfusion; g roup 2 (N = 15), prostaglandin E1 intraflap injection of 1 mug immediately after ischemic injury and reperfusion 4 hours later; and group 3 (N = 5), t he sham-operated group. Analysis consisted of flap skin survival area measu rements, immunohistochemical study using anti-intercellular adhesion molecu le (anti-ICAM-1) monoclonal antibody, and histological evaluation including endothelium-sticking leukocytes at 24 hours and 5 days after reperfusion. The group treated with prostaglandin E1 showed immunohistochemical findings with decreased expression of ICAM-1 on the surface of the endothelium, and histology showed significant (p < 0.01) reduction of leukocyte adhesion at 24 hours and 5 days after reperfusion. These two factors were considered t o play a role against ischemia-reperfusion injury, and led to improved surv ival of the flap. These results suggest that prostaglandin E1 may increase flap survival and may have a protective mechanism against ischemia-reperfus ion injury by decreasing leukocyte-endothelial cell adhesion through decrea sed expression of ICAM-1.