Piscator M
Environ Health Perspect. 1984 Mar;54:175-9. doi: 10.1289/ehp.8454175.
Four groups of cadmium-exposed persons, from different workplaces and with different types of exposure, have been followed for periods of 9-20 years. In one group the total observation time is over 30 years, since they were included in Friberg's original study. The studies include determination of inulin or creatinine clearance, protein excretion and specific indicators of renal tubular dysfunction. The results indicate that once tubular dysfunction is established, it is irreversible, even when it is minor. In some persons it was noted that the development of renal dysfunction seemed to be a multistage process. The initial stage is characterized by an increased excretion of low molecular weight proteins like beta 2-microglobulin and ribonuclease. After a period of several years with no or low exposure, there was a relatively sharp increase in excretion of total proteins and albumin and a decrease in glomerular filtration rate. This is interpreted as being the result of further increases in renal concentration of cadmium and in spread of cadmium along the tubules. Metallothionein absorption in the tubules, its catabolism and synthesis must play an important role for the development and progress of the tubular dysfunction. It was not possible to show that a decrease in glomerular filtration rate occurs before low molecular weight proteinuria.
对四组来自不同工作场所、接触类型各异的镉接触者进行了9至20年的跟踪研究。其中一组的总观察时间超过30年，因为他们被纳入了弗里伯格的原始研究。这些研究包括菊粉或肌酐清除率、蛋白质排泄以及肾小管功能障碍的特定指标的测定。结果表明，一旦肾小管功能障碍确立，即使很轻微，也是不可逆的。在一些人身上，注意到肾功能障碍的发展似乎是一个多阶段过程。初始阶段的特征是低分子量蛋白质如β2 -微球蛋白和核糖核酸酶的排泄增加。在数年无接触或低接触之后，总蛋白和白蛋白的排泄相对急剧增加，肾小球滤过率下降。这被解释为肾小管中镉浓度进一步升高以及镉沿肾小管扩散的结果。肾小管中金属硫蛋白的吸收、其分解代谢和合成必定对肾小管功能障碍的发展和进展起重要作用。无法证明在低分子量蛋白尿出现之前肾小球滤过率就已下降。
