Bilateral Testicular Consequences in the Unilateral Vasectomy of Immature Rats

We evaluated the effects of unilateral obstruction of the vas deferens on testicular endocrine and exocrine function in rats. The left vas deferens was ligated and divided in 1-week-old Wistar rats. Additional rats of the same age underwent a sham operation. Bilateral testicular weight and epididymal weight were compared between the vasectomized and sham-operated animals at 4, 8 and 12 weeks postoperation. Intratesticular versus intraabdominal temperature difference, epididymal caudal sperm content (ECSC), motility (ECSM) and in vitro fertilizing capacity (IVF) were compared between the vasectomized and sham-operated animals at 12 weeks postoperation. Serum testosterone response to human chorionic gonadotropin and bilateral testicular weight were significantly smaller in the vasectomized animals than in the sham-operated animals at 8 and 12 weeks postoperation. Bilateral ECSC, ECSM and IVF outcomes were significantly smaller in vasectomized rats than in sham-treated rats 12 weeks postoperatively. Bilateral intratesticular versus intraabdominal temperature differences were not significantly different between the vasectomized and control rats at 12 weeks postoperation. Unilateral obstruction of the vas deferens results in a bilateral defect in spermatogenesis and in the epididymal sperm maturation process.