Three new experimental models of anterior urethral stricture in rabbits.

Background: This study describes and compares three surgical procedures for the construction of urethral stricture (US) models in rabbits. Methods: Forty adult male rabbits were allocated to four groups: 36 rabbits were randomly assigned to three experimental groups, while the remaining 4 were assigned to a sham group. The penis was separated from the rectum. Then along the ventral midline, a longitudinal penile skin incision was made while ensuring that the urethral mucosa was intact and the muscular layer was not completely incised. In group 1 (n=12), ventral semi-circumferential mucosa electrocoagulation of a 1-cm length of the anterior urethra was performed until ulceration occurred. In group 2 (n=12), the ventral urethral mucosa was incised, and electrocoagulation of the dorsal semi-circumferential mucosa was performed. In group 3 (n=12), whole-circumferential mucosa electrocoagulation was performed. In group 4 (n=4), no special treatment was performed. Four weeks later, urethrography, urethroscopy, and histological evaluation were carried out. Results: The weights of the rabbits in the four groups were comparable. There was no significant difference between groups 2 and 3 with regard to operative time, but the operative time in these groups was significantly longer than that in group 1 (group 2 Conclusions: Compared with the semi-circumferential procedures, the whole-circumferential procedure had a higher success rate. Therefore, this procedure seems to have potential for the construction of long-segment rabbit US models.