[Mechanisms of oxygen transport across biological membranes]

Using metallic microelectrodes, intracellular measurements were performed of changes in O2 concentration for spherical oocytes of hens by their replacement from normal (PO2=150 torr) to hyperoxic (to 600 torr) conditions, and vice versa. The curves of O2 influx and efflux were recorded in pulse regime of the working electrode polarization. The character of these curves can be expressed by the following equations: m(t)==c==e=y1t+y0 and m (t) =e-y1t+v0+c, where v1 is determined by the coefficient of cell membrane permeability for O2. Valid differences were shown between values of v1 for oxygen influx and efflux which vanish after the action of cyanides. It is suggested that O2 transport into the cell involves a base component which may be physical diffusion, and an additional component which can be depressed by cyanides.