Regional distribution of pyridoxal-5'-phosphate in developing and mature brains and its depletion in pyridoxine deficiency.

A study was made of (a) the distribution of the coenzyme pyridoxal-5'-phosphate (PLP) in four discrete regions of developing and mature rat brains and (b) the effect of dietary pyridoxine deficiency on the distribution. There was an increase in PLP concentration of all the regions from infancy to adulthood. Highest concentration of PLP was found in the medulla and pons in both infants and adults. Pyridoxine deficiency resulted in a more marked reduction of PLP in all regions of the neonatal brain as compared with those in the mature brain. This is consistent with the vulnerability of the developing brain to nutritional stresses.