The measurement of the diffusion of oxygen through respiring tissue

Abstract

The validity of Warburg''s equation for diffusion of oxygen through tissue slices is discussed. A method of studying the respiration of tissue slices is described which can be used to measure both their QO2 and their critical or limiting O2 concentration. The results obtained with this method support the validity of Warburg''s equation. The equation is used to calculate values for the diffusion coefficient of O2 through respiring liver, heart and kidney slices, and values for the minimum concentration of O2 necessary to saturate a terminal oxidase in those tissues. Unexpectedly high values for the diffusion coefficients and possibly for the critical oxygen concentration of the terminal oxidase were obtained. Their significance is discussed.