目的：Benoff等人在2004年發表左側精索靜脈曲張的不孕病人，是因兩側的睪丸內，鎘金屬濃度增加累積所造成。所以，我們以實驗導致左側精索靜脈曲張的老鼠，探討在不同的時間內，其睪丸內鎘濃度的變化。材料與方法：以24隻Sprague-Dawley的成鼠作左側腎靜脈的部分結紮，成功造成精索靜脈曲張的當實驗組。另外16隻成鼠進行假手術當對照組。分別在術後的2、4、8及12週取下兩組的兩側睪丸，進行鎘金屬濃度的分析。結果：對照組老鼠左側睪丸內的鎘金屬濃度從低於偵測值（小於0.01ppb），到最高2.4±0.9(ng/g)；而施於手術導致左側精索靜脈曲張的老鼠（實驗組）則明顯高於對照組，而且未施於手術之右側睪丸，鎘含量也是低於偵測值。結論：這是國內、外第一篇文章證實左側精索靜脈曲張的老鼠，其同側睪丸內的鎘金屬濃度會增加。而鎘是會造成睪丸細胞凋亡的有毒金屬，這是否與精索靜脈曲張造成男性不孕的機轉有關，尚待進一步的研究探討。

OBJECTIVES: In 2004, Benoff et al. reported the increased accumulation of cadmium (Cd) in testes of infertile men with left varicocele. We used an animal model to determine whether the cadmium concentration changed in the ipsilateral testis of rats with an experimentally induced left varicocele.MATERIALS AND METHODS: An experimental left varicocele (ELV) was created by partial ligation of the left renal vein in 24 adult male Sprague-Dawley rats as the study group. An additional 16 rats that underwent a laparotomy and left renal vein handling without ligation served as the sham control group. Six rats of the study group (n = 6) and 4 rats of control group (n = 4) were sacrificed at 2, 4, 8, and 12 weeks following varicocele creation. The left testicular tissue of both groups was sampled. We used atomic absorption spectrophotometry with a graphite furnace for the Cd analysis.RESULTS: The numbers of rats in the varicocele group were 4, 5, 6, and 5 at 2, 4, 8, and 12 weeks, respectively, after varicocele creation. The Cd concentration in the left testis was lower than the detectable level to 2.4 ± 0.9 ng/g dry weight in the control group, but in the varicocele group, it was significantly higher than in the control group. However, there were no significant differences among the various treatment times.CONCLUSIONS: This is the first report to prove that the Cd concentration in the ipsilateral testis of rats with a left varicocele was higher than that in the control group. Further additional studies are needed to investigate the relationship of Cd and varicocele-induced male infertility.