| Tissue engineering and regenerative medicine are the most advanced techniques for treating the failure of tissue and organ. The one of their technique basis is a feasible cellular scaffold. Many researches indicate that the best scaffold is a natural extracellular matrix (ECM). Now, the scientists find that the component and structure of ECM in homologous tissue and organ are identical. Furthermore, the ECM of some heterogeneous tissue is analogous, for example, many tissues and organs of pig and mankind. As a result, preparing the natural porcine ECM scaffold, which is heterotransplanted to renew and replace the function of exhausted tissue and organ, is an important way in the biological research.of cellular matrix.In our research, we studied the methods of preparing two kinds of the porcine acellular matrix and turne out scaffolds. One kind was dermal acelluar matrix (DAM) scaffold; the other kind was bladder acellular matrix (BAM) scaffold. The preparation process of the porcine DAM scaffold is to rinse with SDS or Triton X-100 following the extraction with Trypsin or Dispase. Based on the usual Meezan's method, we modified preparation process of the porcine BAM scaffold through adding RNAse to reinforce DNAse's lysis function. The pathological section conformed that our preparation materials had no cells and cellular fragment, only retained ECM.The other research was that our preparing scaffolds were heterotransplanted to mend the bladder defect of the experimental rabbits as patches. Through examining the samples of the graftpatches' growth, our object was to testify whether the acellular matrix is a kind of effective cellular scaffold for the regeneration of bladder wall.In our animal experiment, we made animal models of bladder defect with partial cystectomy for rabbits. The rabbits were divided into three groups to execute mending: the first group use porcine DAM scaffold; the second group use porcine BAM scaffold; the third group was experimental control, only simply partial cystectomy. During the three months after operation, there is no distinction on the post-operation reaction, living condition, micturition and chemical examination including blood routine, urine routine, electrolyte and renal function among the three groups. With the statistical analysis, the bladder capacity of post-operation more than pre-operation in experimental group rabbits, however, less in the control group rabbits; no significant difference between two experiment groups, however, significant difference between the experiment group and the control group.When we observed the anastomosis of the bladder tissue and matrix scaffold in the different time, we found that the newborn bladder cells or tissues gradually developed from margin to center in the scaffold. When the neonate tissue gradually converged towards center and formed new bladder wall, the scaffold were gradually degraded and replaced by constructed tissue. The pathological sections indicated that each layer of bladder tissue regenerated and reconstructed with time. It is a common repair process of operate trauma in control group. The experiment group differed from the control group, but two experiment groups were no distinction.At the first week, transitional epithelial cells and smooth muscle cells (SMCs) came into the scaffold edge and scaffold center was no cell. Erythrocyte, leucocyte and monocyte infiltrated to the anastomosis of the bladder tissue and matrix scaffold. A mass of uro-epithelial cells appeared in the second week and went through stratification, proliferation, differentiation, and construction with time. The epithelium cells displayed normal feature until 1 month at the edge of scaffold, however, cells of graft center needed longer time. The scaffold was substituted by normal bladder wall about three months.By the immunohistochemistry staining means, a -actin staining displayed initial SMCs at the second week, afterwards, through the regeneration, differentiation, organization, arrangement, and combination the smooth mu...
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