Various influecnes of amino acids upon ChE activity in the brain of latent cerebral local anaphylactic rabbits (LCLA rabbits) and normal ones were studied. 1) The ChE activity in the brain of LCLA rabbits accelerated stronger than that of normal rabbits, but after adding amino acid it fell to normal value or less. 2) By addition of amino acid the ChE activity redueces both in normal rabbits and LCLA rabblts, but it was more marked in the latter. 3) The intensity of the straint of amino acids for the ChE activity is the largest by glutamine to normal rabbits. Aspartic acid, γ-aminobutyric acid, asparagine, glutamic acid follows. To LCLA rabbits glutamine effects excellent and then asparagine, γ-aminobutyric acid, aspartic acid, glutamic acid. 4) If the density of adding amino acid solution is changed in glutamine and glutamic acid, they show a maximum straint at M/10. In glutamine it shows respectable straint even at M/200. 5) The influence of glutamine upon the ChE activity in the brain of LCLA rabbits showed straint even at M/100 and at M/200 it became equal with the level of normal rabbit brain. This is found to be almost the same value as the deficient value of amino nitrogen in LCLA rabbit brain.