Miyahara T, Nemoto S, Kaji T, Yamada H, Takeuchi M, Mori M, Kozuka H
Toxicol Lett. 1986 May;31(2):113-23. doi: 10.1016/0378-4274(86)90004-4.
Subcutaneous (s.c.) and intraperitoneal (i.p.) injection and oral administration of calcium (Ca) into rats increased Ca content of liver compared with control rats. When liver cytosol was filtered through a Sephadex G-75 column, zinc (Zn) content of metallothionein (MT)-like protein fraction was several times higher in Ca treatment than in control. Zn and copper (Cu) content of high-molecular (HM) and moderate-molecular (MM) fractions and Cu content of MT fraction was unaffected by Ca treatment. Zn in MT fraction showed two peaks in the direct-connection method of high-performance liquid chromatography to atomic absorption spectrophotometer (AAS). The retention time of these two peaks agreed with those of Zn or cadmium (Cd) in MT fraction of liver cytosol obtained from Zn- or Cd-administered rat. These results show that MT-like protein containing Zn is induced by Ca. In conditions showing a slight increase in liver Ca and a significant decrease in serum Ca by synthetic [Asu1,7] eel calcitonin (CT) injection, gel filtration of liver cytosol obtained from CT-treated rats showed a higher content of Zn and a higher radioactivity of [3H]cystine than that from control injection. This suggests that CT causes an increase in liver Ca and results in induction of MT-like protein containing Zn by Ca.
与对照大鼠相比，给大鼠皮下（s.c.）、腹腔内（i.p.）注射钙（Ca）及口服钙均可增加肝脏的钙含量。当肝脏胞质溶胶经葡聚糖G - 75柱过滤时，钙处理组中金属硫蛋白（MT）样蛋白组分的锌（Zn）含量比对照组高几倍。高分子（HM）和中等分子（MM）组分的锌和铜（Cu）含量以及MT组分的铜含量不受钙处理的影响。在高效液相色谱直接连接原子吸收分光光度计（AAS）的方法中，MT组分中的锌呈现两个峰。这两个峰的保留时间与从给予锌或镉的大鼠肝脏胞质溶胶的MT组分中的锌或镉（Cd）的保留时间一致。这些结果表明含钙的MT样蛋白是由钙诱导产生的。在通过注射合成的[Asu1,7]鳗鱼降钙素（CT）导致肝脏钙略有增加而血清钙显著降低的情况下，对CT处理大鼠的肝脏胞质溶胶进行凝胶过滤显示，其锌含量和[3H]胱氨酸放射性均高于对照注射组。这表明CT会使肝脏钙增加，并导致由钙诱导产生含锌的MT样蛋白。
