Bladder extracellular matrix transplantation into bladder defects: an experiment study

Purpose:To evaluate feasibility of using homologous bladder extracellular matrix (ECM) graft to repair bladder defect in rabbit model.Methods:The bladder extracellular matrix was made using bio chemistry technique. 27 New Zealand rabbits underwent bladder partial cystectomy (20%～50%) and the bladder defect was repaired with ECM 1.5 times size of the defect; 6 control animals underwent partial cystectomy (40%～50%); and 6 comparison animals underwent partial cystectomy (40%～50%)and the bladder defect was repaired with homogeneous bladder tissue.Results:In experiment group histological evaluation showed that urothelium cell covered all ECM outer surface in 10 days after transplantion and all bladder wall components existed in ECM graft region following 1 month. At 3 months, the morphological examination found good smooth muscle regeneration except nerve tissue. Other biochemistry examination and urine dynamics showed no significant difference between the experimental and control animals.The mean bladder capacity in the control rabbits was significantly smaller (P 0.05 ) than that before transplantion. The comparison animals' bladder grafts developed putrescence during 3～5 days after transplantation.Conclusions:Bladder extracellular matrix should be ideal material to repair bladder defect.