Nickel induced structural and functional alterations in mouse Leydig cells in vitro.

The present study was aimed at investigating effects of nickel (NiCl(2)) on secretion of testosterone (T), cell viability, ultrastructure and apoptosis in mouse Leydig cells. Testosterone release was measured after 48h of culture with 15.67, 31.25, 62.5, 125, 250, 500 and 1000µmol/L NiCl(2) or without NiCl(2) using radioimmunoassay. Cell viability was assessed by a MTT (metabolic activity assay). Quantification of apoptotic cells was performed using TUNEL assay and the ultrastructural changes were analyzed using transmission electron microscopy. The viability was decreased after addition of ≥250µmol/L NiCl(2). A concentration-dependent depression of T production was observed. The percentage of apoptotic cells was significantly increased only after addition of 125, 250 and 1000µmol/L NiCl(2). After addition of ≥250µmol/L NiCl(2) higher incidence of euchromatin was observed. Lipid droplets and vacuoles in cytoplasm were increased after addition of ≥125µmol/L NiCl(2). NiCl(2) induced decrease in numbers of mitochondria and smooth endoplasmic reticulum after treatment with ≥500µmol/L NiCl(2). Our findings suggest a negative effect of NiCl(2) on steroidogenesis, viability, apoptosis and ultrastructure of mouse Leydig cells.