Background: We used an animal model of experimental varicocele to investigate the effects on the ipsilateral testis during the progression of experimental varicocele in rat.
Material/Methods: Experimental varicocele was induced by partial ligation of the left renal vein in rats. Rats in each control group were subjected to a sham operation. After different periods of varicocele creation (6, 12, and 18 weeks), each animal’s left testis was extirpated, and Johnsen’s score, ultrastructure of seminiferous tubules, intratesticular testosterone concentration, and the germ cell apoptotic index of each left testis were compared between the experimental and control groups.
Results: Johnsen’s score and intratesticular testosterone concentrations in each experimental varicocele group were significantly lower than those in the corresponding control groups (P<0.05) and showed significant declines as the duration of varicocele gradually increased; the apoptotic index showed an opposite tendency. Ultrastructural injury of seminiferous tubules gradually became severe as the duration of varicocele gradually increased.
Conclusions: Experimental varicocele caused progressive impairment of the ipsilateral testis; apoptosis mediated the pathophysiological processes of dyszoospermia.

Keywords: rat, Varicocele, Spermatozoa - pathology, Testis - ultrastructure, Testosterone - metabolism, Varicocele - pathology