Analysis of testicular-internal spermatic vein variation and the recreation of varicocoele in a Sprague-Dawley rat model

Many laboratories tried to recreate the varicocoele model have met with varied success. To recreate a consistent varicocoele model by exploring the anatomic variability of the testicular-spermatic venous system in Sprague-Dawley (SD) rats. Seventy-two sexually mature SD male rats were randomly divided into three groups containing 24 rats per group. Partial ligation of the left renal vein and internal spermatic vein (ISV) communicating branches to common iliac vein and ISV communicating branches ligation (RVISVCBCIV) or partial ligation of the left renal vein and ISV communicating branches ligation (RVISVCB). The results showed that the mean diameter of the left ISV was significantly increased in the RVISVCBCIV group compared with the control and RVISVCB groups (p < 0.001). Using ISV as the reference, the sensitivity of varicocoele was 71.43%, and the specificity was 80%. In addition, the positive predictive value was 83.33%, and the negative predictive value was 66.67%. Sperm count, motility, Johnsen score and the spermatogenic cell density were lower in the RVISVCBCIV group compared with the control (p < 0.01). The apoptotic index was higher in the RVISVCBCIV group compared with control groups (p < 0.01). The RVISVCBCIV provides a more effective method for establishing a varicocoele-induced model.