Time course of ICAM-1 expression and leukocyte subset infiltration in rat forebrain ischemia.
The time course of ICAM-1 expression and leukocyte subset infiltration was studied in a model of CNS reperfusion injury in adult rats. Leukocyte adhesion and infiltration, mediated in part by intercellular adhesion molecule-1 (ICAM-1), appears to potentiate CNS reperfusion injury. The timing and relationship between ICAM-1 staining and leukocyte infiltration postglobal CNS ischemia is unknown. Reversible forebrain ischemia was produced in 32 adult Sprague-Dawley rats using the two-vessel occlusion model with histologic analysis performed at specific intervals postischemia: 1, 3, 6, 12, and 24 h, 4 and 7 d, or sham-operated controls (n = 4 each group). Monoclonal antibodies against ICAM-1 (1A29 and TM8), a specific granulocyte (PMN) (HIS48), and a specific monocyte/macrophage (M phi) (ED1) were used. No specific leukocyte and only rare ICAM-1 vessel immunoreactivity was observed in sham controls. ICAM-1: Significant expression in microvessels beginning at 1 h with additional diffuse CA1 pyramidal layer staining beginning at 4 d. Leukocytes: No PMN cells and rare M phi identified at 6 and 12 h. By 24 h: moderate infiltrate in areas of ICAM-1 expression of PMN and M phi. At 4 and 7 d: only M phi accumulation, cellular morphology now similar to microglia. The results of this study indicate that early and persistent ICAM-1 expression occurs following CNS ischemia with associated leukocyte infiltration.
Clark
W M
WM
Department of Neurology, Oregon Health Sciences University, Portland 97201, USA.
Lauten
J D
JD
Lessov
N
N
Woodward
W
W
Coull
B M
BM
D000818:Animals; D001923:Brain Chemistry / Q000276:immunology; D002545:Brain Ischemia / Q000276:immunology / Q000378:metabolism* / Q000473:pathology*; D002465:Cell Movement; D007150:Immunohistochemistry; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis* / Q000737:chemistry / Q000276:immunology; D007700:Kinetics; D007962:Leukocytes / Q000737:chemistry / Q000276:immunology / Q000473:pathology*; D008297:Male; D017628:Microglia / Q000737:chemistry / Q000276:immunology; D009474:Neurons / Q000737:chemistry / Q000276:immunology; D016548:Prosencephalon / Q000276:immunology / Q000378:metabolism* / Q000473:pathology*; D051381:Rats; D017207:Rats, Sprague-Dawley
D018799:Intercellular Adhesion Molecule-1