Hepatic Encephalopathy is Associated with Decreased Numbers of Receptors for Excitatory Aminoacid Neurotransmitters

  • P. Ferenci
  • C. S. Pappas
  • E. A. Jones


The pathogenesis of hepatic encephalopathy (HE) is still poorly understood. In a recent editorial Zieve1 mentioned 20 different metabolic abnormalities which are associated with liver failure and which could conceivably contribute to the mediation of this syndrome. Several observations have suggested that in liver failure impairment of cerebral neurotransmission may occur. In the “false neurotransmitter hypothesis” of the pathogenesis of HE proposed by Fisher and Baldessarini2 it was assumed that a decrease in the cerebral content of dopamine and the presence of competitive inhibitors of dopamine impaired the function of the dopaminergic neurotransmitter system and thereby induce neural inhibition. However an increasing body of evidence at variance with the hypothesis has been generated.3 Numerically dopaminergic neurons constitute only a small fraction of the total number of neurons in the central nervous system (CNS). In contrast, the number of neurons which mediate aminoacid-induced neurotransmission constitute a very large proportion of the total neurons in the CNS.4


Hepatic Encephalopathy Kainic Acid Fulminant Hepatic Failure Synaptic Membrane Hepatic Coma 
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Copyright information

© Plenum Press, New York 1984

Authors and Affiliations

  • P. Ferenci
    • 1
  • C. S. Pappas
    • 2
  • E. A. Jones
    • 2
  1. 1.I. Universitätsklinik für Gastroenterologie und HepatologieViennaAustria
  2. 2.Liver Diseases Section NiaddkNIHBethesdaUSA

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