[Transformation of the inhaled nitrogen oxides NO and NO2 in animals].

The authors have studied in the lungs and blood the time course evolution of nitrogen oxides (NO and NO2) administered by inhalation, in rabbits and guinea pigs. NO2 was rapidly oxidized into NO3-. The latter were eliminated within 24 h, the oxidation rate having been variable according to animal species. In presence of NO, the persistence of NO3- beyond 24 h indicates a retardation of the oxidation, NO having to pass previously by the NO2- step.