[Continuous measurement of oxygen consumption in small laboratory animals]

A technique for measuring the oxygen consumption of small laboratory animals suitable for pharmacological and toxicological studies is described. The oxygen consumption of the animal in the respiratory chamber is compensated by means of a photoelectrically operating servo mechanism from an oxygen reservoir. The oxygen supplied is directly recorded via a transducer by an X-Y recorder. The carbon dioxide exhaled by the animal is entirely absorbed. Composition and pressure of air in the respiratory chamber correspond to the physiological medium. The usefulness of this technique is demonstrated by investigations on the effects of epinephrine and morphine on the oxygen consumption of rats.