镉、硒对神经细胞钙稳态及蛋白激酶活性交互影响的体外实验研究

Interaction between Cadmium and Selenium on Calcium Homeostasis and Protein Kinase Activity in Nerve Cells in Vitro

目的 观察镉、硒对神经细胞内〔Ca2 +〕i及蛋白激酶(PKA、PKC)活性的交互影响。方法 以分离神经细胞为研究对象 ,测定不同状态下神经细胞内〔Ca2 +〕i及蛋白激酶 (PKA、PKC)活性。结果 5～ 5 0 μmol/L镉可使神经细胞内〔Ca2 +〕i及PKA活性降低 ,而使PKC活性升高 ;5 0 0 μmol/L镉可使神经细胞内〔Ca2 +〕i及PKA、PKC活性明显升高。 5 μmol/L的硒不引起细胞内〔Ca2 +〕i发生变化 ,对镉所致神经细胞内〔Ca2 +〕i的变化也没有影响。结论 体外实验不适合于硒拮抗镉毒性作用的研究。

Objective To observe the interaction between Cd and Se on 〔Ca 2+ 〕i and protein kinase activity in neurons.Methods We detected the activity of 〔Ca 2+ 〕i and protein kinase(PKA,PKC) in isolated neurons in different conditions.Results The result shows that the Cd dose of 5～50μmol/L decreases intracellular free Ca 2+ concentration(〔Ca 2+ 〕i)and PKA activity,and increases PKC activity,however the Cd dose of 500μmol/L increases significantly 〔Ca 2+ 〕i in nerve cell,and PKA,PKC activity.The Se dose of 5μmol/L does not cause the variation of 〔Ca 2+ 〕i in nerve cell,and has no effect on the variation of intracellular free Ca 2+ concentration caused by Cd in neurons.Conclusion The present study shows that study in vitro is not suitable for the study that Se inhibits Cd toxicity.