Balthrop J E, Dameron C T, Harris E D
Biochem J. 1982 May 15;204(2):541-8. doi: 10.1042/bj2040541.
Soluble fractions from chick liver and aorta were examined for copper-binding proteins. In liver a zinc-binding thionein appeared to be the major binding protein for copper. Aortic tissue contained only traces of this thionein protein. Unlike liver, moderate amounts of soluble copper in aorta showed no association with macromolecules. Chicks fed on copper-deficient diets for 8 days had one-third the liver copper concentrations of controls. Aortic copper concentration was decreased only slightly, but the activity of lysyl oxidase, a copper-dependent enzyme in aorta, was decreased significantly. Treating the deficient chicks with CuSO4 (1 mg/kg) restored liver copper rapidly. The increase correlated with the binding of copper to a 10 000-mol.wt. component in the soluble fraction. Aortic copper concentrations responded much less to the CuSO4 treatment, but lysyl oxidase activity was again measurable in the tissue. Radioactive isotopes of copper bound almost exclusively to the 10 000-mol.wt. component in liver and to components of mol.wt. 30 000 or above in aorta. Hardly any of the administered radioactivity appeared with the 10 000-mol.wt. components in aorta, and none was found with unbound copper. The 30 000-mol.wt. components in aorta showed superoxide dismutase activity that was sensitive to NaCN. They also showed the highest specific activity of copper of any other aorta component. A clear distinction was seen between the metabolism of copper in liver and aortic tissues. Whereas a copper thionein, metallothionein, was a major component in the liver pathway, it is doubtful that this protein plays a major role in the intracellular metabolism of copper in aortic tissue.
对鸡肝脏和主动脉的可溶性组分进行了铜结合蛋白检测。在肝脏中，一种锌结合硫蛋白似乎是铜的主要结合蛋白。主动脉组织中仅含有痕量的这种硫蛋白。与肝脏不同，主动脉中适量的可溶性铜与大分子无关联。以缺铜日粮喂养8天的雏鸡，其肝脏铜浓度仅为对照组的三分之一。主动脉铜浓度仅略有下降，但主动脉中一种铜依赖性酶——赖氨酰氧化酶的活性显著降低。用硫酸铜（1毫克/千克）处理缺铜雏鸡后，肝脏铜迅速恢复。这种增加与铜与可溶性组分中一种10000道尔顿分子量的成分结合相关。主动脉铜浓度对硫酸铜处理的反应要小得多，但该组织中的赖氨酰氧化酶活性再次可测。铜的放射性同位素几乎完全与肝脏中10000道尔顿分子量的成分结合，与主动脉中30000道尔顿分子量及以上的成分结合。给予的放射性几乎没有出现在主动脉中10000道尔顿分子量的成分中，未结合的铜中也未发现放射性。主动脉中30000道尔顿分子量的成分表现出对氰化钠敏感的超氧化物歧化酶活性。它们还显示出主动脉其他任何成分中最高的铜比活性。肝脏和主动脉组织中铜的代谢存在明显差异。虽然铜硫蛋白（金属硫蛋白）是肝脏途径中的主要成分，但该蛋白在主动脉组织铜的细胞内代谢中是否起主要作用值得怀疑。
