Undernutrition during the gestation and suckling periods does not cause any loss of pyramidal neurons in the CA2-CA3 region of the rat hippocampus.

The total number of hippocampal pyramidal cells in the CA2-CA3 region are reported to be unaffected by undernutrition during the gestation period. We hypothesised that this may not be the case in animals subjected to a lengthier period of undernutrition. Wistar rats were undernourished from conception until 21 post-natal days-of-age and killed for examination at 21 and 62 days-of-age. There were between 180-212 thousand pyramidal cells in control animals at both 21 and 62 days of age. Twenty-one-day-old undernourished rats had about 152 thousand such cells and this increased to about 206 thousand by 62 days-of-age. Analysis of variance tests on these data revealed a significant main effect of age but no group or interaction effects. Our experiments, therefore, confirm that these hippocampal pyramidal neurons are relatively spared the adverse effects of undernutrition during early life, even when this is extended to include both the gestation and suckling periods.