Bergeron M, Layrargues G P, Butterworth R F
Laboratory of Neurochemistry, André-Viallet Clinical Research Centre, Hôpital Saint-Luc (University of Montreal), Quebec, Canada.
Metab Brain Dis. 1989 Sep;4(3):169-76. doi: 10.1007/BF01000293.
Concentrations of the branched-chain amino acids (BCAAs) valine, leucine, and isoleucine and the aromatic amino acids (AAAs) phenylalanine and tyrosine were measured in three areas of dissected brain tissue obtained at autopsy from nine cirrhotic patients who died in hepatic encephalopathy. The controls were an equal number of subjects free from neurological, psychiatric or hepatic diseases, matched for age and time interval from death to freezing of autopsied brain samples. Amino acids were measured using high-performance liquid chromatography with fluorimetric detection. In brain tissue of cirrhotic patients, no changes in BCAA concentrations were observed compared with controls. On the other hand, phenylalanine levels were found to be increased 141% in prefrontal cortex, 86% in frontal cortex and 26% in caudate nucleus, and tyrosine content was increased by 71% in prefrontal cortex and 28% in frontal cortex with no significant increase in caudate nucleus. Alterations in the concentration of AAAs may lead to disturbances of monoamine neurotransmitters in brain. Such changes could play a role in the pathogenesis of hepatic encephalopathy resulting from chronic liver disease in man.
对9例死于肝性脑病的肝硬化患者尸检时获取的脑组织的三个区域，测定了支链氨基酸（BCAAs）缬氨酸、亮氨酸和异亮氨酸以及芳香族氨基酸（AAAs）苯丙氨酸和酪氨酸的浓度。对照组为数量相等的无神经、精神或肝脏疾病的受试者，在年龄以及从死亡到尸检脑样本冷冻的时间间隔方面进行了匹配。使用配有荧光检测的高效液相色谱法测定氨基酸。与对照组相比，在肝硬化患者的脑组织中未观察到BCAAs浓度的变化。另一方面，发现前额叶皮质中的苯丙氨酸水平增加了141%，额叶皮质中增加了86%，尾状核中增加了26%，前额叶皮质中的酪氨酸含量增加了71%，额叶皮质中增加了28%，尾状核中无显著增加。AAAs浓度的改变可能导致脑中单胺神经递质的紊乱。这种变化可能在人类慢性肝病所致肝性脑病的发病机制中起作用。
