摘要The aim of this study was to explore the effects of varicocele on the morphology and function of Leydig cells in the rat testis.Forty male Sprague-Dawley rats were divided into two groups: the experimental group underwent surgery to create a left varicocele(VC),and the control group underwent a sham operation.Serum testosterone and intratesticular testosterone levels were measured using a radioimmunoassay after 4 and 8 weeks of operation.Leydig cells were studied for apoptosis and expression of steroidogenetic acute regulatory(StAR)protein mRNA levels.Serum testosterone levels declined after 4 and 8 weeks of operation but were not significant(P>0.05).However,the intratesticular testosterone levels after 8 weeks were significantly decreased compared with the control group(P<0.01).The mean apoptosis index of Leydig cells in the experimental group was significantly higher than that in the control group after 4 or 8 weeks(P<0.01).StAR mRNA levels in the Leydig cells of the experimental group were significantly lower compared to those of the control group(P<0.01).Our data show that varicocele did impair Leydig cell function by increasing apoptosis and suppressing the expression of the StAR protein.