MODIFICATION OF LEAD METHOD FOR DEMONSTRATION OF ALKALINE PHOSPHATASE ACTIVITY WITH LIGHTAND ELECTRON-MICROSCOPY

Abstract

There have been some methods for the demonstration of alkaline phosphatase activity with a high alkaline pH optimum, using metal salts as a capture reagent. In Takamatsu and Gomoris' methods the precipitates of calcium phosphate were transformed into silver or cobalt phosphate for visualization with light microscope. However, one step reaction is necessary to obtain exact cytochemical results for electron microscopy. Lead ions were first used by Molbert et al. as the capture reagent for this purpose. However, the reaction was carried out below pH 8 and diffusion seemed to occur. Deimling, her co-worker, described a modified lead method conducting the reaction at pH 8.2-9.2 with light microscopy. The present author also tried the lead method and found that the concentration of potassium sodium tartrate, the chelating reagent added to make lead ions stable in alkaline solution, is critical and they used too much tartrate.