OXYGEN CONSUMPTION OF FROG TISSUES UNDER HIGH HYDROSTATIC PRESSURE

The rate of oxygen consumption of some frog tissues was measured under various hydrostatic pressures up to 500 atm. The tissues either intact, minced, or homogenized were immersed in oxygenated Ringers solution in 10 ml syringes without any gas bubbles. The syringes were immersed in water in a pressure vessel with a control in a similar vessel at atmospheric pressure. The partial pressure of the oxygen in the solution was measured with an oxygen electrode before and after a period of a few hours under pressure. In skin, liver, kidney and lung, pressure caused a decrease in oxygen consumption, but in skeletal muscle there was a 25% increase because the muscles went into a contracture. This increased the demand for oxygen in spite of a presumed inhibition of the oxidative process itself. To account for the inhibition there is presumably some point in the oxidative process which involves an increase in volume. The burning of glucose to CO2and water does result in a slight increase in volume. © 1969.