The separation of the epididymis and the abnormal attachment of the gubernaculum cause undescendence in the rat testes.

Abstract

Epididymal anomalies are common in cryptorchid patients. This led us to consider that anomalies of the epididymis, to which the gubernaculum is attached, or abnormal attachment of the cranial end of the gubernaculum, could lead to cryptorchidism. Twenty-eight male Sprague-Dawley rats were divided into two groups: In Group 1 rats (n=14), the epididymis was isolated from the testis, and in Group 2 rats (n=14), the gubernaculum was isolated from the epididymis and re-attached to the tail of the epididymis. In both groups, the non-operated testes were used as the control. In Group 1, cryptorchidism rates were 1/14 in the control testes and 8/14 in the operated testes (p<0.01). In Group 2, cryptorchidism rates were 0/13 in the control testes and 6/13 in the operated testes (p<0.01). Cryptorchidism was seen when the epididymis was loosely or non-connected to the testis and the gubernaculum was attached solely to the epididymis (mimicking anomalies of ductal fusion) and when the gubernaculum was attached to the tail of the epididymis (mimicking anomalies of ductal suspension). Therefore epididymal anomalies and abnormal attachment of the gubernaculum may play a role in the undescendence of the testes in the rats.