酪氨酸(Tyr)、苯丙氨酸(Phe)与色氨酸(Trp)三种具有芳香环侧链的氨基酸代谢紊乱所引起的中枢神经递质失衡可能是肝昏迷的重要原因之一。在肠道细菌的氨基酸脱羧酶作用下,芳香族氨基酸可脱羧生成相应的芳香胺类,如酪胺、苯乙胺等。正常情况下,由肠道进入机体的大部分芳香胺类可为肝细胞线粒体的单胺氧化酶氧化分解。当严重肝脏病变时,由于肝机能衰竭,加之有门静脉分流,可使大量芳香胺未经解毒而直接进入体循环。酪胺与苯乙胺 One of the important reasons for hepatic coma is the imbalance of the transmitter of the central nervous system caused by the disorder of the amino acids with three kinds of aromatic ring side chains, tyrosine (Tyr), phenylalanine (Phe) and tryptophan (Trp). Under the action of amino acid decarboxylase of intestinal bacteria, the aromatic amino acids can be decarboxylated to form the corresponding aromatic amines, such as tyramine, phenethylamine and the like. Normally, most of the aromatic amines entering the body from the intestine oxidize and decompose the mitochondrial monoamine oxidase of hepatocytes. When severe liver disease, due to liver failure, coupled with portal vein diversion, can make a large number of aromatic amine directly into the systemic circulation without detoxification. Tyramine and phenethylamine