Ezaki O
Division of Nutrition and Diseases, National Institute of Nutrition, Tokyo, Japan.
J Biol Chem. 1989 Sep 25;264(27):16118-22.
Zn2+ (1 mM), Cd2+ (1 mM), and Hg2+ (0.1 mM) belonging to the IIb group in the periodic table stimulated glucose transport activity and cAMP phosphodiesterase in rat adipocytes. The stimulation of glucose transport was due to the translocation of glucose transporters from the intracellular site to the plasma membrane. However, in intact adipocytes none of these ions stimulated insulin receptor kinase activity or phosphorylation of the 95-kDa subunit of insulin receptor or 170- or 60-kDa proteins at the tyrosyl residues. These proteins were markedly phosphorylated by addition of 0.3 nM insulin which stimulated glucose transport activity as effectively as these metal ions. These results indicate that Zn2+, Cd2+, and Hg2+ mimic insulin action by a post-receptor/kinase mechanism.
元素周期表中IIb族的锌离子（1毫摩尔）、镉离子（1毫摩尔）和汞离子（0.1毫摩尔）刺激大鼠脂肪细胞的葡萄糖转运活性和环磷酸腺苷磷酸二酯酶。葡萄糖转运的刺激是由于葡萄糖转运体从细胞内位点转位到质膜。然而，在完整的脂肪细胞中，这些离子均未刺激胰岛素受体激酶活性或胰岛素受体95千道尔顿亚基或170或60千道尔顿蛋白质在酪氨酸残基处的磷酸化。通过添加0.3纳摩尔胰岛素可使这些蛋白质显著磷酸化，该胰岛素刺激葡萄糖转运活性的效果与这些金属离子一样有效。这些结果表明，锌离子、镉离子和汞离子通过受体后/激酶机制模拟胰岛素作用。
