Intercellular adhesion molecule-1 (ICAM-1) and selectins (E- and P-selectin) mRNAs were determined in individual liver cell types by Northern blot analysis before and after injection of endotoxin. A constitutive expression of ICAM-1 mRNA was found in endothelial cells and Kupffer cells but not in hepatocytes. All three cell types showed upregulation of ICAM-1 mRNA after endotoxin. No constitutive selectin expression could be detected in any liver cell, but endotoxin induced massive synthesis of E- and P-selectin mRNA in endothelial cells and Kupffer cells. The differential expression of cellular adhesion molecules in the liver is consistent with the involvement of selectins in neutrophil rolling in the vasculature and ICAM-1 in transendothelial migration and adherence to parenchymal cells.