研究稀土离子对巨噬细胞功能的影响。方法 :采用亚硝酸盐分光光度法及电子自旋捕获法检测稀土离子存在下大鼠巨噬细胞呼吸爆发时产生的氧自由基·O2 -及·OH的变化。结果 :在实验浓度范围内 (10 -7～10 -4 mol·L-1) ,La3+、Y3+、Tb3+均表现为抑制呼吸爆发的作用 ,La3+的作用尤为明显。Ce3+在浓度低于 10 -5mol·L-1时也表现为抑制作用 ,但在浓度高于 10 -5mol·L-1时作用相反。结论 :稀土离子在较低浓度时都能抑制活性氧自由基的生成。较高浓度时 ,作用相反。 Study of rare earth ions on macrophage function. Methods: Nitrite spectrophotometry and electron spin trapping method were used to detect the changes of oxygen free radicals · O2 - and · OH produced by respiratory burst of rat macrophages in the presence of rare earth ions. Results: La3 +, Y3 + and Tb3 + all showed respiratory burst inhibition in the concentration range of 10 -7 ~ 10 -4 mol·L-1. The effect of La 3 + was especially evident. Ce3 + also showed inhibitory effect at concentrations below 10 -5 mol·L-1, but at concentrations above 10 -5 mol·L-1. Conclusion: Rare earth ions can inhibit the formation of reactive oxygen species at lower concentration. The higher the concentration, the opposite effect.