Effects of Cadmium Exposure on Leydig Cells and Blood Vessels in Mouse Testis

Environmental exposure to cadmium (Cd) contributes to a decline in the quality of human semen. Although the testis is sensitive to Cd exposure, the mechanism underlying how cadmium affects the testis remains to be defined. In this study, male mice were treated with intraperitoneal injections of 0, 0.5, 1.5 and 2.5 mg CdCl₂/kg/day for 10 days, respectively. Both the testicular weight and the 3β-HSD activity of Leydig cells were significantly reduced with the administration of 2.5 mg CdCl₂/kg/day. The height of endothelial cells in the interstitial blood vessels significantly increased with the use of 2.5 mg CdCl₂/kg/day compared with the control. Western blot data showed that the protein levels of CD31, αSMA, caveolin and Ng2 increased with cadmium exposure, and this increase was particularly significant with the administration of 2.5 mg CdCl₂/kg/day. CD31, αSMA, caveolin and Ng2 are related to angiogenesis. Based on our data, cadmium exposure may stimulate the proliferation of the mural cells and endothelial cells of blood vessels, which may lead to abnormal function of the testis.