Abel J, de Ruiter N, Kühn-Velten W N
Abteilung Toxikologie, Heinrich-Heine-Universität, Düsseldorf, Federal Republic of Germany.
Arch Toxicol. 1991;65(3):228-34. doi: 10.1007/BF02307313.
The present study aimed at investigating whether previously reported interstrain differences of mice in testicular susceptibility to cadmium toxicity can be attributed to different metallothionein expression in the testes and other organs. Furthermore, purified Leydig cell systems were employed to identify a testicular compartment capable to respond specifically to exogenous cadmium by increased metallothionein expression. It was shown that species differences in testicular damage after cadmium administration can not be explained by differences in cadmium-induced stimulation of hepatic and renal metallothionein. In contrast to these organs, no metallothionein response to cadmium was observed in testicular homogenates. However, both freshly isolated and purified rat Leydig cells and a murine tumor Leydig cell line are not only able to synthesize metallothionein under basal conditions, but also respond to exogenous cadmium by increased synthesis of metallothionein (35S-cysteine incorporation) and an increased Mt-mRNA content. Extracts from freshly isolated and purified rat Leydig cells contained a cadmium-binding component which eluted in gel chromatography with the same properties as metallothionein. It was concluded that the use of purified cell systems is a valuable tool to investigate possible targets of cadmium toxicity.
本研究旨在调查先前报道的小鼠品系间睾丸对镉毒性易感性的差异是否可归因于睾丸及其他器官中金属硫蛋白表达的不同。此外，采用纯化的睾丸间质细胞系统来确定睾丸中能够通过增加金属硫蛋白表达对外源镉产生特异性反应的区域。结果表明，镉给药后睾丸损伤的种属差异不能用镉诱导的肝脏和肾脏金属硫蛋白刺激差异来解释。与这些器官不同，在睾丸匀浆中未观察到对镉的金属硫蛋白反应。然而，新鲜分离和纯化的大鼠睾丸间质细胞以及小鼠肿瘤睾丸间质细胞系不仅能够在基础条件下合成金属硫蛋白，而且对外源镉的反应是金属硫蛋白合成增加（35S-半胱氨酸掺入）以及Mt-mRNA含量增加。新鲜分离和纯化的大鼠睾丸间质细胞提取物含有一种镉结合成分，其在凝胶色谱中的洗脱特性与金属硫蛋白相同。得出的结论是，使用纯化的细胞系统是研究镉毒性可能靶点的有价值工具。
