[Pathogenesis of portal systemic encephalopathy].

Hepatic encephalopathy is a neuropsyquiatric syndrome associated to multifactorial metabolic disruptions. Several physiopathogenic theories have been proposed. In this review authors explain and analyze most of theses theories which include ammonia, mercaptans, false neurotransmitters, gamma aminobutiric acid, endogenous benzodiazepins, and zinc deficiency as well as some of the new biochemical concepts of neurotransmission.