The effect of experimental varicocele on the testis of adolescent rats.

Experimental varicocele was created by partial ligation of the left renal vein in rats 4, 7 and 12 weeks old to compare the effects of varicocele on the testis at different times of onset: prepuberty, adolescence and adulthood. We examined the testes at 4 and 8 weeks after creation of the varicocele. The experimental groups of rats 4 and 12 weeks old showed slight testicular changes compared to control groups at 4 and 8 weeks postoperatively. In the 7-week group left testicular weight was significantly decreased (1.03 +/- 0.31 gm.) compared to that of the control group (1.51 +/- 0.12 gm.) at 4 weeks. The seminiferous tubular diameter in the left testis also was significantly reduced (219 +/- 37 microns) compared to that of the control group (270 +/- 14 microns). Histological changes, such as degeneration of germinal epithelium, tubular atrophy, Sertoli cell hyperplasia and interstitial edema, were observed more frequently in the 7-week group. At 8 weeks these changes were less significant. Our results suggest that varicocele during adolescence has the most damaging effects on the testis in rats.