Prenatal undernutrition: effects on behavior, brain chemistry and neuroanatomy in rats

The behavior and cerebral effects of prenatal protein-calorie undernutrition were investigated in newborn and postweanling rat pups. At birth, prenatally undernourished (PU) animals showed a deficit in body weight; however, by day 15 the difference was diminished and not significant. On days 13-18, PU pups required more trials for reversal learning of a water-escape response in a T-maze than control (C) pups; however, on days 31-35, there were no difference between groups when trained to learn an active-avoidance response. Assessment of brain development showed that at birth, DNA and protein content was severely reduced in PU animals; however, normalization was noted in regional sections of the brain at 35 days of age. Brainstem reticular cells from PU pups at birth show less dendritic arborization and less terminal branching cells from C pups. The results are discussed in terms of a delayed rate of maturation.