[Canine urethra as a model for experimental studies on urethral strictures (author's transl)]

Of all commonly used laboratory animals, the dog seems especially suited for transurethral experiments on the urethra when using normally available urological instruments. Because of its particular anatomy only the pelvic portion of the urethra in male dogs is available for study. In animals weighing at least 20 kg this segment is wide enough to permit insertion of instruments of up to F 24 size. Anatomically, this segment corresponds to the proximal segment of the bulbous portion of the urethra in man, i.e. there is no corpus cavernosum urethrae surrounding the urethra. Experiments in this segment require a perineal urethrostomy, the construction of which is associated with a high complication rate. The pelvic urethra of the male dog does not differ structurally from that of the female dog. Experiments on the female canine urethra can therefore be performed equally well and with less complications. Urethral strictures can be simply and effectively created by circular transurethral electrocoagulation of the urethral wall. With extensive urethral wall coagulation, temporary complete urinary retention may be observed postoperatively, which is due to extensive edema of the affected area.