The artificial conduit for urinary diversion in rats: a preliminary study

Small intestinal submucosa forms a scaffold for tubular construction. The aim of this study was to build the artificial conduit using small intestinal submucosa (SIS) and 3T3 fibroblasts for urinary diversion in rats.

3T3 fibroblasts were multiplied to a total of 10(9). Two groups consisted of three Wistar rats each. The left ureters were separated from the bladder and anastomosed to the proximal end of the tubular scaffold. No splitting of the ureteral junction or drainage was done. The distal end of the scaffold was implanted into a previously performed channel in the abdominal wall. Cell-seeded grafts were used in the first group and acellular SIS scaffolds in the second group. Rats were sacrificed after 2 and 4 weeks. X-ray pyelography was performed. Hematoxylin and eosin staining was prepared from conduit cross sections.

All animals survived the observation. An inflammatory reaction was observed within the peritoneal cavity in both groups. It was difficult to dissect the adhesions in the cell-seeded group. The ureteral-conduit anastomoses were tight in five cases, except there was leakage and pseudocyst formation after 14 days in one cell-seeded graft. No ureterohydronephrosis was observed in two acellular conduits after 14 or 30 days, and in one case of a cell-seeded graft. A neovascularisation process was observed in the acellular conduit after a month. Multilayered epithelium covered the conduit lumen near the anastomosis at the distal end of acellular conduit, a small islet-forming epithelial layer was observed after a month.

3T3 fibroblasts cannot serve as a "feeder layer" for ureteral augmentation. It seems that there is no need to split the ureteral-conduit junction. An SIS scaffold was used for tubular construction for urinary diversion in an animal model.