[Histochemical study of the cholinesterases of the human cerebral hemispheres in early ontogeny]

Abstract

Histochemical studies have been made on acetylcholinesterase and butyrylcholinesterase of human isocortex in early ontogenesis. The data obtained confirm the earlier findings concerning the predominant localization of acetylcholinesterase in the intermediate layer of the isocortex. Significant increase in the enzymic activities was observed approximately to the 10-11th weeks of embryogenesis. Significant differences were found in the localization of the cholinesterases in the isocortex itself and in the nuclei of the striopallidal system, i.e. the nearest subcortical formations which presumably account for the main cholinergic afferentation to the cortex. The data obtained are discussed in relation to evolutionary trends in the development of the brain.