title: Mental fatigue-induced decrease in levels of several plasma amino acids.
abstract: To investigate the relation between plasma amino acid levels and mental fatigue, we measured the plasma concentrations of 20 amino acids in 9 healthy volunteers before and after a fatigue-inducing mental task session for 8 hr. As fatigue-inducing mental tasks, the subjects performed an advanced trail making test, a Japanese KANA pick up test, and a mirror drawing test. As a control, 8-hr relaxation session was performed in the same subjects at an interval of 4 weeks. Immediately after the fatigue session, the plasma levels of branched-chain amino acids, tyrosine, cysteine, methionine, lysine, and arginine were below those after a relaxation session. The values for other blood parameters including total protein, albumin, glucose, and total cholesterol did not show any differences between the 2 sessions. These results indicate that mental fatigue may be characterized by a decrease in the plasma level of these amino acids.
authors.affiliation: Department of Physiology, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Mizuno
authors.forename: M
authors.initials: M
authors.lastname: Tanaka
authors.forename: S
authors.initials: S
authors.lastname: Nozaki
authors.forename: K
authors.initials: K
authors.lastname: Yamaguti
authors.forename: H
authors.initials: H
authors.lastname: Mizuma
authors.forename: T
authors.initials: T
authors.lastname: Sasabe
authors.forename: T
authors.initials: T
authors.lastname: Sugino
authors.forename: T
authors.initials: T
authors.lastname: Shirai
authors.forename: Y
authors.initials: Y
authors.lastname: Kataoka
authors.forename: Y
authors.initials: Y
authors.lastname: Kajimoto
authors.forename: H
authors.initials: H
authors.lastname: Kuratsune
authors.forename: O
authors.initials: O
authors.lastname: Kajimoto
authors.forename: Y
authors.initials: Y
authors.lastname: Watanabe
mesh_terms: D000328:Adult; D000596:Amino Acids / Q000032:analysis / Q000097:blood*; D000597:Amino Acids, Branched-Chain / Q000032:analysis / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism; D001921:Brain / Q000378:metabolism / Q000503:physiopathology; D001923:Brain Chemistry / Q000502:physiology; D002784:Cholesterol / Q000097:blood; D015536:Down-Regulation / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D005222:Mental Fatigue / Q000097:blood* / Q000503:physiopathology*; D009483:Neuropsychological Tests; D012063:Relaxation / Q000502:physiology; D012709:Serum Albumin / Q000378:metabolism; D013997:Time Factors
chemical_list: D000596:Amino Acids; D000597:Amino Acids, Branched-Chain; D001786:Blood Glucose; D012709:Serum Albumin; D002784:Cholesterol