| ObjectiveNerve injury by trauma will lead the dysfunction of the appropriate target organ. Therefore, the reconstruction should be made to the injured nerve. It depends on the rehabilitation of the sense and motor targeted by injured nerve to evaluate the reconstructed nerve. It is our goal in the field of neuroscience to explore nerve grafts to bridge the nerve gap between the two stumps of the damaged nerve trunk when direct stitch cant be done. For years, nerve grafts from natural and artificial synthetic materials were developed. Certain progress and better results have been got in the course of experiments. Some problems have still been unsolved in these grafts. For example; immune repulsive reaction, cancer genecity, neuroma and so on. During recent years, the tissue engineering gives us some hopes to achieve in the artificial nerve grafts. In our experiment, a natural extracellular matrix scaffold of nerve was made using the tissue engineering way of hypo-tonic - chemical detergent. We use this nerve scaffold as a nerve graft to bridge the 1cm nerve gap successfully. Some data have been represented to choose the effective nerve grafts for clinical work.MethodsWistar rats'sciatic nerve was cut and fixed. Then the nerve was put into Tris - HCL buffer. The Schwann cell and cells in the sheath was bloated off by hypo - tonic buffer. Then the Wistar rat sciatic nerves was treated by tritonX - 100 to make the Schwann cell debris a-cellular from nerve with co - work of other reagernts such as proteinase inhibitors(aprotinin,leupeptin,pepstatin A), Dnase , Rnase and so on under conditions of certain temperature and pH. The acellular nerve graft and the fresh nerve were fixed with formaldehyde. And then they were dealed with dehydration, embedding regularly, slicing etc. The specimen were stained in HE. At the same time, the specimen were also semi - thick sliced and stained with toluidine blue. Scanning electron microscope and electron microscope were used to e-valuate the differentiation between the acellular nerve and the fresh nerve. The animals were clarified into two groups. One group is auton-erve group,the other is experimental group. These animals were feed for three months. The graft and the distal segment were evaluated by histology and electron microscope.ResultsARSN was more white than the fresh nerve in general. ARSN wont draw back without the fixation. Its elasticity is similar with the fresh nerve. In light microscope, the axons and Schwann cell sheath disappear in the cross section of ARSN. The Schwann cell basal membrane was left alone. In cross section, it looked like a network. In the longitudinal section of ARSN, typical long basal membrane tube can be viewed. The same result was also got in toluidine blue stainedspecimen. The axon, sheath ,Sehwann cell nucleus were all out. There was no cells in the basal membrane. None of debris in the basal mem-barane tube was seen by the evaluation of scanning electron microscope and electron microscope. After the SD rat's sciatic nerve gap was bridged with the ARSN made from Wistar rat sciatic nerve. No affection occurred. We make our evaluations after breeding these animals for 3 months. The operated foot could run forcefully. Its tipitoes can separated when walking. The foot can drawback when being needled. ARSN was assimilated into autonerve when opening the operation part. The ARSN was fixed after being incised out. The specimen were made into semi - thick cross section. They were stained with toluidine blue. Many nerve fibers can be seen in cross section. They were bundled regularly. No neuroma was seen in specimen. Sehwann cell membrane enwrapped the axon in the shape of lamina. The Sehwann cell had a normal shape and its nuclear was by the cell border. In the distal segment, many mature fibers were bundled orderly in the cross section of the specimen stained by toluidine blue.ConclusionIn our experiment, natural ECM scaffold of peripheral nerve was made successfully. This nerve scaffold has an advantage of bio...
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