International braz j urol
Print version ISSN 1677-5538
DOMINGOS, André Luís Alonso et al. Expression of VEGF and collagen using a latex biomembrane as bladder replacement in rabbits. Int. braz j urol. [online]. 2012, vol.38, n.4, pp. 536-543. ISSN 1677-5538. http://dx.doi.org/10.1590/S1677-55382012000400014.
OBJECTIVE: To investigate the VEGF expression and collagen deposition using a latex biomembrane as bladder replacement in rabbits. MATERIALS AND METHODS: After partial cystectomy, a patch of a non-vulcanized latex biomembrane (2 x 2 cm) was sewn to the bladder of rabbits with 5/0 monofilament polydioxanone sulfate sutures in a watertight manner. Groups of 5 animals were killed at 15, 45 and 90 days after surgery and the bladder was removed. Sections of 5µm were cut and stained with picrosirius-red in order to estimate the amount of extracellular matrix in the graft. To confirm the presence of VEGF in tissues, protein expression was determined by immunohistochemistry. RESULTS: No death, urinary leakage or graft extrusion occurred in any group. All bladders showed a spherical shape. A progressive reduction in the amount of collagen occurred in the graft area and was negatively and linearly correlated with time (p < 0.001). VEGF expression was higher in grafted areas when compared to controls at 15 and 45 days after surgery and decreased with time (p < 0.001). CONCLUSION: The latex biomembrane as a matrix for partial bladder replacement in rabbits promotes temporary collagen deposition and stimulates the angiogenic process.
Keywords : Latex; Collagen; Urinary Tract; Tissue-engineering.