PERICELLULAR P-O-2 AND O-2 CONSUMPTION IN MONOLAYER CELL-CULTURES

The current study was based on the uncertainty as to how well monolayer cell cultures growing in customary polystyrene dishes are supplied with O-2. For dishes maintained in an air-5% CO2 atmosphere at 37 degrees C, microelectrode measurements revealed that the pericellular steady-state P-O2 was 78 mm Hg in confluent bovine endothelial, 110 mm Hg in rat renal mesangial, and 0 (<0.2) mm Hg in renal (LLC-PK1 and LLC-MK(2)) or hepatic (HepG2, Hep3B) epithelial cell cultures. These measured P-O2 values were in good agreement with those calculated from Fick's law of gas diffusion, applied for the present culture conditions (one-dimensional O-2 diffusion, 0.52 cm medium height), the individual cell layer density and the tissue-specific rate of O-2 utilization. Our results provide reasons to speculate that conventional monolayer culturesd in an air-5% CO2 atmosphere. Diffusion-limitations of cellular O-2 availability are to be taken into consideration when tissue cultures are used to study P-O2-dependent processes.