Alterations in D-amino acid levels in the brains of mice and rats after the administration of D-amino acids.
To mutant ddY/DAO(-) mice lacking D-amino-acid oxidase activity and normal ddY/DAO(+) mice, five D-amino acids (D-Asp, D-Ser, D-Ala, D-Leu and D-Pro) were orally administered for two weeks, and the D-amino acid levels were examined in seven brain regions. The levels of D-Asp markedly increased in the pituitary and pineal glands in both strains. In the ddY/DAO(+) mice, the levels of the other D-amino acids did not significantly change in most of the brain regions. While in the ddY/DAO(-) mice the levels of D-Ser significantly increased in most of the brain regions except for the cerebrum and hippocampus. The levels of D-Ala and D-Leu increased in all regions but the levels of D-Pro did not significantly change. The same five D-amino acids were intravenously injected into Wistar rats and the D-amino acid levels in their brains were examined for 60 min after the administration. The levels of D-Asp markedly increased in the pineal gland 3 min after the administration, while the levels of D-Ser, D-Ala, and D-Pro increased both in the pineal and pituitary glands, the levels of D-Leu increased in all brain regions. These results are useful for the elucidation of the origins and regulation of D-amino acids in the mammalian body.
Morikawa
A
A
Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan.
Hamase
K
K
Inoue
T
T
Konno
R
R
Zaitsu
K
K
D000596:Amino Acids / Q000008:administration & dosage* / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000378:metabolism*; D001923:Brain Chemistry / Q000187:drug effects*; D003605:D-Amino-Acid Oxidase / Q000172:deficiency*; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D051381:Rats; D017208:Rats, Wistar
D000596:Amino Acids; C485958:Dao1 protein, mouse; D003605:D-Amino-Acid Oxidase