Mice lacking d-amino acid oxidase activity display marked attenuation of stereotypy and ataxia induced by MK-801

The behavioral effects produced by MK-801 (0.4 mg/kg) were compared in mutant DAO−/− mice lacking d-amino acid oxidase activity and normal DAO+/+ mice. Mutant mice display marked diminution of stereotypy and ataxia induced by MK-801 compared to normal mice. Because the d-serine level in the brain of mutant mice is significantly higher than that of normal mice, the elevated d-serine in the brain of mutant mice could antagonize MK-801-induced stereotypy and ataxia.