Reconstruction of the canine pelvic nerve and its application to bladder transplantation

The pelvic nerve (PN) plays a crucial role in control of bladder function. However, repair of the PN during operation or transplantation of the urinary bladder preserving PN control has never been reported. This study was undertaken to explore the possibilities of restoring PN function to the canine bladder after PN-PN reattachment and of transplanting the bladder while preserving PN function. Responses of the bladder to electrical stimulation of the PN were examined in dogs that had undergone PN-PN reattachment or auto-transplantation of the bladder with PN-PN reattachment. Cystometry was performed in dogs that had undergone bladder transplantation. Eighteen months after unilateral PN-PN reattachment, stimulation of each of five PNs sutured in five dogs elicited elevation of bladder pressure. Twelve months after bilateral PN-PN reattachments in five dogs, eight of 10 PNs stimulated elicited elevation of bladder pressure. Three of five dogs that had undergone auto-transplantation of the bladder showed a long survival. Nine months after the operation, each of the six PNs stimulated in the three dogs elicited elevation of bladder pressure. Voiding reflex was observed in two of the three dogs on cystometry. All the 13 dogs examined above preserved sufficient bladder capacity and all but one demonstrated small volume of residual urine. The above results indicate that the function of the PN to the canine bladder can be restored after PN-PN reattachment and that transplantation of the bladder preserving control of the PN is possible.