水上 浩明

We previously generated oxytocin (OXT)-deficient mice and oxytocin receptor (OXTR)-deficient mice. Impaired social behaviors were observed in these mice, so they may be useful as animal models for studying the regulatory mechanism of social behavior by the OXT/OXTR system in the brain. In the present review, we aimed to overview our previous works to unravel the mechanism(s) by which OXTR deficiency leads to the impairment of social behaviors; for example, abnormalities in maternal behavior and/or social memory observed in mice deficient in the OXTR will be presented. By analyzing the brain of the OXTR-modified yellow fluorescent protein knock-in mice histologically, OXTR-expressing neurons were observed conspicuously in brain regions that are related to social behaviors. We focus on the characteristics of the regions containing neurons with prominent Oxtr gene expression in the present manuscript and discuss on the mechanisms through which OXT exerts its effects on social behaviors.