Effect of maternal vitamin B-6 deficiency on specific regions of developing rat brain: amino acid metabolism.

Amino acid metabolism may be adversely affected by vitamin B-6 deficiency. The effects of a maternal deficiency of vitamin B-6 on concentrations of amino acids in substantia nigra (SN), caudate nucleus/putamen (C/P) and cortex (CORT) in progeny were studied. Female albino rats were fed diets containing either 0.6 (deficient) or 7.0 (control) mg pyridoxine x HCl (PN x HCl) per kilogram diet ad libitum throughout growth, gestation and lactation. Paralleling a significant decrease in body weight, pups in the deficient groups began to show gross neurological symptoms of the deficiency at approximately 11 days of age. Analysis of brain regions at 15 days of age showed that the deficiency resulted in decreased concentrations of alanine and serine in SN, C/P and CORT. Often these changes were more pronounced in one or two of the regions analyzed. At 1 and 3 hours after an intraperitoneal injection of 100 mg PN x HCl per kilogram body weight into deficient pups, concentrations of cystathionine, leucine, isoleucine, valine, alanine and serine in brain regions remained similar to preinjection values. However, within 3 hours postinjection, glycine concentrations had decreased and were similar to control levels in SN and C/P.