Tetrazolium Stains for Diphosphopyridine Nucleotide (DPN) Diaphorase and Triphosphopyridine Nucleotide (TPN) Diaphorase in Animal Tissue.

Abstract

Sections are incubated in solutions containing tetrazolium salts and either DPN or TPN together with substrates and cofactors necessary for the action of one or more DPN or TPN linked dehydrogenases. Reduced DPN (or TPN) serves as a substrate for its specific tissue diaphorase which in turn reacts with the tetrazolium salt to deposit an insoluble highly colored formazan in the tissue at sites of diaphorase activity. The stains serve not only to localize the sites of enzyme activities but also bring out certain details of microscopic anatomy difficult to visualize in ordinary preparations.