The role of plasma amino acids in hepatic encephalopathy.

The dog with an end-to-side portacaval shunt has a plasma amino acid pattern similar to that in man with chronic liver disease and encephalopathy. When dogs with end-to-side portacaval shunts manifested symptoms of hepatic encephalopathy, superior caval catheters were placed and one of three solutions was infused. Whereas almost all animals given a commercially available synthetic amino acid mixture died, a special mixture formulated to normalize plasma amino acids was associated with 100 percent survival and few neurological symptoms. The results suggest that manipulation and normalization of plasma amino acids in animals with hepatic failure may be efficacious in providing adequate nutrition while minimizing hepatic encephalopathy. Moreover, these experiments may shed some light on the mechanism of human hepatic encephalopathy.