The glycoprotein laminin is a component of the extracellular matrix and seems to be of considerable importance for cellular adhesion. In static cell cultures laminin revealed a profound influence on migration and proliferation of cultured endothelial cells. Coating of coverslips with laminin was found to have a profound and long-lasting effect on the adhesiveness of endothelial cells exposed to experimental fluid shear stress. By changing the seeding density of the cells per cm2 we could stimulate endogenous laminin production to a level that increased resistance of the monolayer against rheological shear stress by 200%.