Use of abdominal wall with mesothelium as a substrate for reconstitution of urinary bladder wall: replacement of the mesothelium by the urothelium and complete bladder wall reconstruction.

OBJECTIVE: The urinary bladder has considerable regenerative ability and may enable reconstitution of the urinary bladder if used appropriately.
MATERIAL AND METHODS: Rat urinary bladders were allotransplanted onto the inner surface of the abdominal wall with the urothelium facing the mesothelial cells. The ureters, urethra and blood supply were left intact.
RESULTS: A week after the operation, the mesothelium of the abdominal wall was replaced by the urothelium from the donor urinary bladder and a cyst was formed, the inner surfaces of which were completely covered with the urothelium. After a few months, the submucosal tissue and muscular layer had also moved to cover the wall, forming an almost complete urinary bladder. The mucosal membrane formed complex folds, which was probably due to overgrowth of the epithelial cells and the submucosal connective tissues. The area derived from the abdominal wall showed only minimal shrinkage, whereas the abdominal wall from which the mesothelium had been removed showed significant shrinkage.
CONCLUSION: This method is potentially useful for the reconstruction of urinary bladders.