Plasma phenylethanolamine in hepatic encephalopathy.

It has been suggested that amines other than octopamine may be involved in the pathogenesis of hepatic encephalopathy. Plasma phenylethanolamine has been determined by a radioenzymatic method in twenty-six biopsy-proven cirrhotics with or without encephalopathy and in seven normal adults. Phenylethanolamine plasma levels correlated statistically with the presence of liver cirrhosis and severe coma. These results are consistent with the false neurotransmitter hypothesis of hepatic encephalopathy.