Species differences in methaemoglobin production after addition of 4-dimethylaminophenol, a cyanide antidote, to blood in vitro: a comparative study.

Methaemoglobin production after addition of DMAP to blood of various species, has been studied in vitro. The study was undertaken both with blood, as taken, and after equilibration with atmospheric oxygen. Considerable interspecies variation in methaemoglobin production was found. When the initial rate of methaemoglobin formation was considered only marmoset and human blood showed any marked degree of inhibition by equilibration with atmospheric oxygen.