Dikov A, Dimitrova M, Krieg R, Halbhuber K J
Institute of Experimental Morphology and Anthropology, Bulgarian Academy of Sciences, Sofia.
Cell Mol Biol (Noisy-le-grand). 1999 Mar;45(2):241-8.
A new tetrazolium method for the histochemical demonstration of gamma-glutamyl transpeptidase is proposed. The method is based on a newly synthesized substrate-gamma-L-glutamic acid-1-hydroxy-4-naphthylamide, which upon the enzyme hydrolysis liberates 1,4-aminonaphthol--a powerful reducing agent that reduces tetrazolium salts quickly and quantitatively to deeply colored, water-insoluble formazans, precipitating on the sites of the enzyme activity and marking them accurately. The redox reaction is quick enough and does not need any auxiliary electron-acceptor. The method is very fast and convenient for the histochemical visualization of the enzyme.
