A technique for measuring carbon monoxide uptake in mice

Abstract

A new method has been developed for measuring carbon monoxide (CO) uptake in mice. Each animal was placed in a syringe and allowed to rebreathe a mixture of CO and helium (He) for 60 s. CO uptake was determined from a comparison of CO and He concentrations before and after rebreathing. Weight specific CO uptake increased with body weight in CBA mice weighing between 20 to 35 gr. In larger trice, size dependence was less marked, although a slight fall in CO uptake was observed in older animals. Anaestbesia reduced ventilatory rate and CO uptake to a variable extent. The method is reproducible, non-invasive and does not require anaestbesia, consequently, it can be used to study serial changes in lung function. It is sensitive enough to detect lung damage in CBA mice following 16 Gy total body irradiation. Values of diffusing capacity obtained for mice using this method are consistent with published values.