OBJECTIVETo investigate the effect of nonylphenol (NP) on testosterone secretion of Leydig cells.

METHODSA primary culture system of Leydig cells was set up, followed by identification of Leydig cells with 3beta-HSD staining. After treatment with different concentrations of NP, testosterone secretion was detected and morphological examination was performed.

RESULTSFollowing treatment with NP, morphologic changes of Leydig cells were detected, with decreased cell density at high doses of NP. Testosterone increased at lower concentrations of NP while decreased at high concentrations of NP.

CONCLUSIONLower doses of NP can stimulate the secretion of testosterone, but increased exposure to NP will inhibit testosterone secretion of Leydig cells. Besides, high concentrations of NP can cause death of Leydig cells in vitro.