Iodonitrotetrazolium chloride has been used to visualise dehydrogenase enzyme activity histochemically. As the enzyme removes hydrogen from the substrate it is transferred to a hydrogen acceptor, usually a co-enzyme. From the co-enzyme it is transferred to the tetrazole, which is consequently reduced to its insoluble and intensely coloured formazan. The formazan of INT is red.
R. D. Lillie.
Conn's Biological Stains
Williams & Wilkins, Baltimore, MD., U.S.A.
Aldrich chemical catalogue, 1992
Aldrich Chemical Company, Milwaukee, WI, USA.
Enzyme Histochemistry and its application to the study of neoplasms
Academic Press, New York, NY, USA