Influence of several drugs on the in vivo and in vitro activity of mammalian hepatic azo-reductase

Abstract

The ability of a variety of drugs to influence liver azo-reductase activity of rabbits, rats, and guinea pigs in vitro was determined. Only nitrofurantoin showed a marked stimulatory activity in the three species. There was no appreciable inhibitory activity with any of the drugs tested. Determination of azo-reductase activity in vivo after pretreatment of the animals with phenobarbital and nitrofurantoin showed that there was an appreciable increase only in the azo-reductase activity of rats with phenobarbital, and only rabbits showed a marked decrease in azo-reductase activity with nitrofurantoin. Under the same conditions there was an appreciable increase in the excretion of N-acetylated sulfanilic acid by phenobarbital-pretreated rats and guinea pigs, while with nitrofurantoin rabbits showed an increase and rats a large decrease in the excretion of N-acetylated sulfanilic acid.