Experimental model for the quantitative estimation of transendothelial transport in vitro; a two-compartment system

A two-compartment system was set up for the measurement of macromolecules, particles and water transfer through the monolayers of cultured endothelial cells. Experimental parameters like differential hydrostatic and osmotic pressures (delta P and delta pi, respectively) concentration gradients, temperature could be controlled. The experiments were carried out, on a cellular line of bovine aortic endothelium produced in our laboratory. Morphological and immunological investigations attested the differentiation of these cells grown on a porous support membrane separating the two compartments. The system allowed morphologic check up on the continuity of endothelial monolayer and ultrastructural studies. Hydraulic conductivity determined for endothelial monolayers was 6.86 +/- 0.85 cm. sec-1 X cm H2O-1 X 10(-7) at delta P = 10 mm Hg and 8.23 +/- 0.80 cm. sec-1 X cm H2O-1 X 10(-7) at delta P = 30 mm Hg, which proves an adequate functional integrity. Investigations using successive radioactive pulses on the same culture were possible without notable residual radioactivity between pulses.