L-Selectin and Leukocyte Function in Skeletal Muscle Reperfusion Injury

HYPOTHESIS Treatment with anti–L-selectin monoclonal antibody will reduce venular neutrophil-endothelial rolling (flux and velocity) and adhesion associated with ischemia reperfusion injury in rat skeletal muscle. DESIGN Prospective, randomized experimental trials. SETTING Basic science research laboratory. MATERIALS Male Wistar rats weighing 109±5 g (mean±SEM). INTERVENTIONS Gracilis pedicle muscle flaps were elevated and microcirculation was observed by intravital microscopy. Two groups were evaluated: (1) the control group, which received 4 hours of global ischemia, and (2) the experimental group, which received 4 hours of global ischemia, plus treatment with anti–L-selectin monoclonal antibody 30 minutes before reperfusion. MAIN OUTCOME MEASURES The number of rolling and adherent leukocytes in postcapillary venules were counted in the 2 groups at baseline and at 1 through 5, 10, 15, 20, 30, 45, and 60 minutes of reperfusion. RESULTS Treatment with the monoclonal antibody to L-selectin significantly reduced the number of rolling leukocytes (flux) at 2 through 5, 20, 30, 45, and 60 minutes of reperfusion compared with controls (P