Concentration and Distribution of "Encephalin" in the Brain of Humans, and Animals

Abstract

Colorimetric assay of a large number of human and animal brains for "encephalin" revealed a rather uniform pattern of intracerebral distribution in various spp. There was no appreciable difference between the encephalin content and its distribution in the brains of "normal" and "psychotic" humans. No major changes were observed under the influence of various hormones, adrenalectomy, hypophysectomy, convulsive drugs, electrical stimulation of the brain, narcotics, conditions of stress, acetylcholine, and N-free diet. Only the injn. of dihydroxphenylalanine was followed by a very marked temporary increase of the colorimetric readings, which suggests either a selective absorption of this substance by the brain or its conversion into encephalin.