Journal of Inherited Metabolic Disease

, Volume 13, Issue 2, pp 151–155 | Cite as

The effect of plasma valine, isoleucine and leucine on the control of the flux through tyrosine- and tryptophan-hydroxylase in the brain

  • F. A. Hommes
  • J. S. Lee


The effect of increasing blood levels of valine, isoleucine and leucine on the fluxes through tyrosine and tryptophan hydroxylase in brain has been calculated and analysed in terms of flux control coefficients. It is concluded that any beneficial effect of increasing the concentration of these amino acids in phenylketonuria patients is not due to a decrease in brain phenylalanine or an improved neurotransmitter synthesis through tyrosine or tryptophan hydroxylase.


Internal Medicine Tyrosine Beneficial Effect Tryptophan Leucine 
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Copyright information

© Society for the Study of Inborn Errors of Metabolism and Kluwer Academic Publishers 1990

Authors and Affiliations

  • F. A. Hommes
    • 1
  • J. S. Lee
    • 1
  1. 1.Department of Cell and Molecular BiologyMedical College of GeorgiaAugustaUSA

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