Perinatal MK-801 treatment affects age-related changes in locomotor activity from childhood to later adulthood in rats.

Neuronal degeneration underlying the pathology of schizophrenia is already present during childhood. However, most of these studies were done in adult humans or animals. The present study therefore investigated age-related changes of behavior in an innovative version of the Open Field Maze following perinatal chronic administration of the noncompetitive N-methyl-D-aspartate antagonist MK-801. The waxing and waning pattern of locomotor activity during aging with a peak around the age of 90 days was profoundly attenuated by MK-801. MK-801 further reduced locomotion and body weight in mature rats. However, it increased explorative behavior in immature rats. Therefore, the chronic perinatal administration of MK-801 seems to be a model to investigate the pathological mechanisms of psychomotor retardation and body weight dysregulation in schizophrenia.