Somatostatin: A New Therapeutic Agent for Treatment of Hepatic Encephalopathy?

In advanced cirrhosis of the liver Fischer et al. (1975) have described distinctive patterns of amino acids; the aromatic amino acids phenylalanine and tyrosine are elevated and the branched chain amino acids valine, leucine and isoleucine are decreased, therefore the ratio of the molar concentrations of branched chain to aromatic amino acids is reduced. It has been suggested that this amino acid imbalance causes hepatic encephalopathy, since the branched chain and aromatic amino acids compete for entry across the blood-brain barrier. As a consequence of the reduced amino acid ratio the concentrations of aromatic amino acids in the brain increase and lead to elevated levels of false neurotransmitter substances such as octopamine and phenylethanolamine (Smith et al. 1978; James et al. 1976). In cirrhosis of the liver insulin (IRI) and glucagon (IRG) levels are elevated. It has been suggested that the increased glucoregulatory hormones are responsible for the amino acid imbalance and the catabolic state in advanced liver cirrhosis. (Soeters and Fischer 1976).