PURPOSE: To obtain the subject improving agent containing theanine, an amino acid derivative characterisically contained in tea, as an active ingredient, not having a problem on safety, acting on a NMDA type receptor to raise the concentration of Ca in nerve cells, and effective for treating, improving and preventing Alzheimer's disease, etc.
CONSTITUTION: This improving agent contains theanine as an active ingredient. The theanine is preferably dissolved in purified water or physiological saline solution to give an injection solution containing the theanine in a concentration of ≥ approximately 50μm, or furthermore mixed with taurine, royal jelly, inositol, nicotinic acid amide, vitamins, anhydrous caffeine, a granulating agent and a sweetener. The theanine is preferably e.g. a L-glutamic acid-γ-ethylamide of the formula.
NOZAWA AYUMI
TAKIHARA TAKANORI
SAKANE IWAO
KURODA YOICHIRO
