Neonatal corticosterone treatment increases submissiveness in adulthood in mice.

Mice were treated with either a placebo, 100 or 300 mcg/day corticosterone during postnatal Days 3-5 and tested for submissiveness in adulthood. Neonatal corticosterone treatment, regardless of dosage level, resulted in increased adult levels of submissiveness. This effect cannot be ascribed to differences in adult resting corticosterone levels, since neonatal corticosterone- and placebo-treated mice did not differ in the levels of this hormone. Some alternative explanations of this effect of neonatal corticosterone treatment on adult social behavior are discussed.