Glycerolization of Chinese hamster ovary cells in monolayer culture

CHO monolayer cultures were used as a model system to examine the kinetics of cell glycerolization and deglycerolization. Both influx and efflux of [³H]glycerol appear to be first-order processes, the rate of flux being proportional to glycerol concentration. When net flux ceases, the intracellular and extracellular concentrations of glycerol appear to be identical. Influx can be described by a single first-order curve, whereas efflux requires at least two such functions. Flux rates are sensitive to changes in osmolality, the fast efflux component accelerating and the slow component decelerating with increased application of osmotic stress. The rate of influx slows as the temperature drops and as the viscosity of the medium increases. Cells can tolerate a much steeper deglycerolizing gradient at 37 °C than at 0 °C.