Gutiérrez VI, Domínguez MA

Language: Spanish
References: 39
Page: 60-70
PDF size: 120.23 Kb.

ABSTRACT

Hepatic encephalopathy is a neuropsychiatric disorder that occurs in both acute and chronic liver failure. Changes have been attributed to a toxic effect of ammonia and/or manganese that in liver failure accumulate in the brain. A deficit in neurotransmission rather than a primary deficit in cerebral energy metabolism appear to be involved. Neurotransmitter systems implicated in the pathogenesis of hepatic encephalopathy include glutamatergic, gamma-aminobutyric acid-ergic and serotonin neurotransmission, as well as the catecholaminergic and opiod system. The neural cell most vulnerable to liver failure is the astrocyte. The astrocye undergoes characteristic changes known as Alzheimer type II astrocytosis. Further elucidation of the precise nature of these alterationscouldresult in the design ofnovelpharmacotherapies for the prevention and treatment of hepatic encephalopathy.

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