A histochemical method for L-amino acid tetrazolium reductase

Summary Some incubation media were elaborated to demonstrate tissue activity of L-amino acid tetrazolium reductase. These media had as substrate a L-amino acid to which a small amount of L-glutamate was added, well below the concentration used to demonstrate glutamic-dehydrogenase.The specifity of the reactions was assessed by incubations in control media and by studying the effects of some inhibitors. The work was concerned both with the actual pattern of the reaction and with changes initiated in the medium by tissue incubation.It became obvious that in this way an actual visualisation of an enzymatic oxido-reductive activity of various degrees in tissues and organs was possible.