The Influence of Diet-Induced Hyperphenylalaninemia on Molecular Neurochemistry and Learning Behaviour in the Rat

摘要

Hyperphenylalaninemia was induced in Sprague-Hawley albino rats, either prenatally or at weaning, by dietary overloads of 7% L-phenylalanine. The condition was found to lower brain weights and RNA/DNA, Protein/DNA and Protein/RNA ratios but, except for inducing fatigue, did not appear to interfere with the learning of a 6-unit water-maze task. The brain weight differences and fatigue aspect of the water-maze performance disappeared when the phenylalanine diet was withdrawn, and only residual neurochemical effects remained. In lieu of evidence of a permanent retardation in learning behavior, the neurochemical results cannot be used as an explanation of the mental retardation found in human phenylketonuria. (Author)