Division of Radiooncology, Deutsches Krebsforschungszentrum, 69120 Heidelberg, Germany
There exist many different enzyme substrates which give a variety of colors and some of them are suitable for both light and electron microscopy. As with histochemical methods in general, also with immunocytochemical substrates attention must be directed toward the correct histological localization. Reliable localization can be achieved by the selection of suitable procedures and control reactions. Descriptions of some widely used cytochemical substrates for enzyme labels are described. There exist many variations of the original procedures which may be read in the references cited.