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The role of tryptophan in hepatic encephalopathy

Published online by Cambridge University Press:  18 September 2015

C. Aaldijk
Affiliation:
Erasmus Universiteit Rotterdam, destijds keuze-coassistente
W.W. Van Den Broek
Affiliation:
afdeling Psychiatrie van het AZR-Dijkzigt
R.C. Van Der Mast*
Affiliation:
afdeling Psychiatrie van het AZR-Dijkzigt
*
Afdeling Psychiatrie Academisch Ziekenhuis Rotterdam-Dijkzigt, Dr. Molewaterplein 40 3015 GD Rotterdam

Summary

In this review the most important hypotheses for the occurrence of the clinical picture of hepatic encephalopathy are discussed. As possible pathogenetic mechanisms are raised: dysfunction of the serotonergic system due to an increased tryptophan uptake in the brain, an elevated intracerebral ammoniac concentration and glutamine synthesis, and a heightened intracerebral GABA-activity.

The dysregulation of the serotonergic system as a consequence of the increased intracerebral tryptophan uptake is described as one of the most important pathogenetic mechanisms. The elevated intracerebral ammoniac concentration and the elevated intracerebral glutamine synthesis play in this a facilitating role. The similarity in symptomatology of the clinical picture of HE and the serotonergic syndrome support this hypothesis. Due to contradictory research findings the role of the GABA-ergic system and the occurrence of HE remains unclear.

Type
Research Article
Copyright
Copyright © Scandinavian College of Neuropsychopharmacology 1993

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