Histochemical Demonstration of Sites of Choline Esterase Activity.

Abstract

Some choline esterases hydrolyze higher choline esters readily and they also survive to a demonstrable extent the procedures of histological fixation and embedding. It is possible to demonstrate them histo-chemically by incubating slides with the substrate in the presence of a cobalt salt; at the sites of choline esterase activity insoluble cobalt-soap will precipitate which can be transformed into black CoS. The histochemical distribution and properties of choline esterase are described.