A DOUBLE PROTEIN A-GOLD-SILVER STAINING METHOD USING ONE-STEP DEVELOPMENT FOR LIGHT-MICROSCOPY

A simple and useful double staining method has been developed for ligh t microscopic immunohistochemistry. The technique consisted of a seque nce of protein A-gold staining followed by a single silver enhancement procedure, and in this technique reaction products were colored black , and brown or reddish purple, respectively. The results obtained in t he rat pancreatic islets and adenohypophysis in combination with a var iety of histochemical controls have substantiated the specificity, rel iability and reproducibility of the double staining method. The presen t method is simple and economical, since visualization of the reaction products of two different shades can be obtained by a single procedur e.