Effects of prenatal maternal handling and rearing with aunts on behavior, brain weight, and whole-brain serotonin levels.

Abstract

AbstractRats were handled daily throughtout gestation. Their litters and those of nonhandled rats were fostered to nonhandled mothers, half of whom were then housed with a virgin female (aunt). Prenatal handling decreased serotonin levels in 21‐day‐old offspring tested at the trough of the 24‐hr serotonin rhythm. Rearing with aunts resulted in lower brain weights among males, but had no effect on the serotonin levels of weanling rats. Both prenatal handling and rearing with aunts affected scores of female offspring in a reaction‐to‐handling test administered at age 56 days, but an open‐field test yielded only sex differences. Rearing with aunts differentially affected trough serotonin levels at that age, males showing a signficant decrease, whereas female values increased.