ABSTRACT
This chapter describes the in vitro metabolism of nitrate and discusses the in vivo nitrate metabolism and its possible importance in human disease. Nitrate is reduced to nitrite as part of the anaerobic respiratory system in a wide range of organisms and as part of the nitrate assimilation system in a more restricted group of bacteria. Nitrate metabolism by bacteria has been studied in four sites in the body, namely the oral cavity, the stomach, the infected urinary bladder, and the colon. Nitrate is totally nontoxic in humans and other animals but its metabolites, particularly nitrite, cause major toxicity problems particularly in children and in young adults but also possibly in adults. The products of nitrate metabolism may also be of great importance clinically since nitrite may be an important intermediate in the formation of /V-nitroso compounds. The pharmacology of dietary nitrate has been studied extensively by Bartholomew et al.
