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-c-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 < .05). Use of the monoclonal antibody significantly reduced the number of adherent neutrophils at 5, 10, 15, 20, 30, 45, and 60 minutes of reperfusion [P<.05). There was no significant difference in leukocyte velocity. Conclusion: L-Selectin plays a significant role in leukocyte rolling and adherence to venular endothelium in rat skeletal muscle ischemia reperfusion injury.