Maternal deprivation alters growth, food intake, and neuropeptide Y in the hypothalamus of adolescent male and female rats.

Maternal deprivation (MD) for 24 hr during the neonatal period impairs body weight gain in adolescent and adult rats. It has been previously shown that maternally deprived rats consume less standard and carbohydrate-rich diets. Because neuropeptide Y (NPY) is implicated in feeding behavior, we assessed, prospectively, the effects of maternal deprivation, imposed on postnatal days (PND) 3 (DEP3) or 11 (DEP11), on physical development (snout-anal length and body weight gain, measured once a week) and food intake (assessed daily, during the rest and active phases, from PND 23 to PND 51); NPY-immunoreactivity (NPY-ir) in the arcuate nucleus of the hypothalamus was evaluated in male (at PND 52) and female rats in estrous (at PND 53-60). DEP3 and DEP11 male and female adolescents were smaller, lighter, and ate less during the active phase, than their CTL counterparts. This change in food intake was accompanied by reduced NPY-ir in the arcuate nucleus of the hypothalamus. The present results indicate that maternal deprivation had a negative impact on the physical development and feeding behavior of adolescent rats that may be explained by reduced hypothalamic NPY production.