Changes of Gamma-aminobutyric Acid, Glutamic Acid and Aspartic Acid in Various Brain Structures of Cats deprived of Paradoxical Sleep

Abstract

KNOWLEDGE of the role of free amino-acids in the activity of the central nervous system (CNS) and in the basic neural processes of excitation and inhibition has accumulated over a number of years. The pool of free amino-acids in the brain is the source from which amino-acids liberated by the breakdown of proteins are returned¹. The brain has the highest concentration of glutamic acid, gamma-aminobutyric acid (GABA) and aspartic acid, and these compounds do not occur to any significant extent in the other tissues of mammals. GABA especially occurs only in the CNS of mammalian organisms, and it has been shown that this substance has characteristic physiological effects on the CNS (ref. 2). In nervous tissue, as in other organs, the carbon skeleton of non-essential amino-acids is derived ultimately from glucose by way of the citric acid cycle. Active brain transaminases catalyse the reversible amination and deamination of essential and non-essential amino-acids.³.