ISSN:
1432-1440
Keywords:
Anorexia
;
Aromatic amino acids
;
Branched-chain amino acids
;
Dopaminergic neurons
;
Neoplastic diseases
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary Studies in anorectic tumor-bearing rats indicate that anorexia is correlated to imbalances of neutral amino acids in blood and CNS. Consequently plasma amino acids of patients with neoplastic and non-neoplastic internal diseases were studied during phases of anorexia; special regard was given to the precursors of dopamine and serotonin. Anorectic patients were compared to non-anorectic patients with neoplasia. During anorexia, plasma levels of valine and leucine and hence the ratio of the molar concentrations of Val+Leu+Ile/Phe+Tyr were significantly decreased in each anorectic patient as compared to non-anorectic patients whose ratios were always within the normal ranges. As aromatic and branched-chain amino acids compete for penetration of the blood brain barrier, the decrease of the amino acid ratio may induce a raised flux of phenylalanine and tyrosine into the CNS which results in an increased activation of dopaminergic neurons — known to cause anorexia.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01782466
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