Effects of maternal dietary restriction in vitamin B-6 on neocortex development in rats: B-6 vitamer concentrations, volume and cell estimates.

Influence of the time of maternal restriction in dietary vitamin B-6 on vitamer concentrations and morphological development of neocortex was examined. Rats were fed ad libitum a vitamin B-6-free diet supplemented with 0.0 or 0.6 mg pyridoxine X hydrochloride (PN X HCl)/kg diet during gestation followed by a control diet (7.0 mg PN X HCl/kg) during lactation or were supplemented with 0.6 or 7.0 mg PN X HCl/kg diet throughout gestation and lactation. During postweaning offspring received the maternal diets fed during lactation. Neocortices of offspring were examined at 30 d of age by liquid chromatography and light microscopy. Vitamin restriction during gestation and 30 d postnatal was the only vitamin B-6-restricted treatment of the three administered that altered B-6 vitamer levels in neocortex; all vitamers were depressed equally. Brain weight and volume of neocortex were not changed significantly by the maternal restrictions imposed. However, each restriction adversely affected neurogenesis and neuron longevity of the neocortex and when expressed as percent reduction from control, neuron longevity was affected more severely than neurogenesis.