endothelial cell cultures incubated with peg-superoxide dismutase and peg-catalase for 24 h and then extensively washed were protected from the damaging effects of reactive oxygen species derived from exogenous xanthine oxidase as judged by two criteria : decreased release of intracellular 51cr-labeled proteins and free radical-induced changes in membrane fluidity , measured by electron paramagnetic resonance spectroscopy of endothelial membrane proteins covalently labeled with 4-maleimido-2,2,6,6-tetramethylpiperidinooxyl .
C0225336
endothelial cell
C0014257
endothelial