A NEW REAGENT FOR THE HISTOCHEMICAL DEMONSTRATION OF ACTIVE CARBONYL GROUPS. A NEW METHOD FOR STAINING KETONIC STEROIDS1

Abstract

A new method for demonstrating carbonyl groups in the lipoid of formalin-fixed tissues is described. The method is based on the reaction of aldehydic and ketonic groups with 2-hydroxy 3-naphthoic acid hydrazide followed by coupling of tetrazotized di-orthoanisidine into the naphtholic ring with the production of a blue, insoluble azo compound. Reaction with certain carbonyl groups of non-lipoid material in nervous tissue, elastic tissue and reticulum is described. Carbonyl-reacting lipoid was found in adrenal cortex, corpus luteum, interstitial cells of testis and syncytium of placenta. The localization in tissue was similar to that previously demonstrated with other methods. Evidence is presented that the carbonyl-containing lipoid in these formalin-fixed glands is in fact ketosteroid.