LEUKOCYTE INVOLVEMENT IN CEREBRAL INFARCT GENERATION AFTER ISCHEMIA AND REPERFUSION

White blood cell involvement in the generation of cerebral infarcts wa s evaluated following ischemia and reperfusion injury in the rat. Cont rol and leukopenic rats (induced by vinblastine, WBC counts < 1500/mm( 3)) were compared in a global forebrain ischemic model after 1 h of is chemia and 1 h 15 min of reperfusion. Cerebral infarcts were defined o n coronal brain sections using Triphenyl tetrazolium chloride (TTC) st aining. Electroencephalographic activity (EEG) and somatosensory evoke d potentials (SSEP) were also compared. Results indicate that the area infarcted in leukopenic rats was significantly less than infarcts gen erated in corresponding controls (21 +/- 16% vs. 70 +/- 16%). In addit ion, EEG was preserved in all leukopenic animals when compared to cont rols, both during ischemia and after reperfusion. The cortical peak co mponent of the SSEP was also better preserved in the leukopenic animal s both during ischemia and at 60 min of reperfusion. These results ind icate white blood cell participation in the generation of cerebral dam age in a model of global forebrain ischemia and reperfusion as indicat ed by TTC staining of cerebral infarcts.