Intercellular adhesion molecule-1 expression and neutrophil infiltration after cerebral ischemia-reperfusion in rats

Objective:To investigate the expression of intercellular adhesion molecule1(ICAM1) and neutrophil infiltration after cerebral ischemiareperfusion in rats.Methods:40 male Wistar rats were randomly divided into 3 groups:control group,sham operation group and cerebral ischemiareperfusion group (reperfusion for 2,4,12,24,48,96 hours postischemia).Immunohistochemical and histological techniques were respectively used to evaluate ICAM1 expression and neutrophil infiltration in focal brain tissue after various duration of reperfusion following middle cerebral artery occlusion(MCAO) for 2 hours in rats.Results:The expression of ICAM1 started to increase after reperfusion for 2 hours,peaked at 48 hours after reperfusion,and continued for 96 hours.Neutrophil infiltration in ischemic tissue increased at 12 hours,and peaked at 48 hours after reperfusion,paralleling the increase in ICAM1 expression.Conclusions:The increased expression of ICAM1 after cerebral ischemiareperfusion is significantly correlated with the degree of the neutrophil infiltration in focal ischemic brain tissue,which may be an important mechanism of ischemiareperfusion damage.