Reproduction of functional smooth muscle tissue and partial bladder replacement

Abstract

Objective To find a means of bladder augmentation that would avoid the complications encountered with the use of bowel segments, using a newly developed acellular biomaterial, the bladder acellular matrix graft (BAMG), as a homologous graft. Materials and methods Thirty‐four rats underwent a partial cystectomy (40–50%) and grafting with a BAMG of equal size. Eleven rats died within the first 72 h, probably from urinary leakage caused by obstruction of the bladder neck with stones or coagula; the surviving 23 were killed at varying intervals after cystectomy and examined. Results After providing initial bladder enlargement, the graft was progressively infiltrated by the vessels and smooth muscle cells of the host; furthermore, the mucosal lining was complete within 10 days. After 4 weeks, all bladder wall components were evident histologically in the graft. The ingrowth was complete after 8 weeks, except for neural regeneration, which was only partial. At 12 weeks, the bladder wall muscle structure in the graft was so well developed that it was difficult to delineate the junction between host bladder and BAMG. Neural regeneration continued to improve. Normal bladder capacities were maintained throughout the study. Conclusion The BAMG appears to serve, without rejection, as a framework of collagen and elastin for the ingrowth of all bladder wall components. The reason for the better acceptance of the BAMG than of other bladder augmentation grafts requires further investigation.

Purinergic signalling in the urinary tract in health and disease

“…Collagenbased and biodegradable materials have also been shown to have regenerative and functional capacities and a bladder acellular matrix graft has been claimed to be successful for augmentation cytoplasty in the rat model leading to structural and functional regeneration of detrusor smooth muscle [568] including contractile activity to electrical field stimulation showing responses to muscarinic, purinergic and adrenergic agonists [557].…”

Epithelial-Differentiated Adipose-Derived Stem Cells Seeded Bladder Acellular Matrix Grafts for Urethral Reconstruction: An Animal Model

“…9,20 After washing with double distilled water for 24 h, the isolated matrices were treated using 1% Triton X-100 (Sigma) and 0.1% ammonium hydroxide with continuous shaking for 14 days to induce cell lysis. The solution was refreshed every 3 days.…”

Tissue engineering in urology

“…21 Rat bladder ECM used as a scaffold in an augmentation model appeared nearly identical to the native bladder at 12 weeks after implantation. Additionally, in vivo functionality of hamster, rabbit and dog bladder ECM grafts demonstrated partial detrusor regeneration with improved compliance and functional capacity in augmented rat bladders when compared to a partial cystectomy bladder in controls.…”