| Objective: With the development of modern society,the rate of trafficaccident and trauma incidence has been increasing year by year. as a result,the patient with peripheral nerve injury and defect in the clinical are more andmore. When the never defect distance <6cm, it can be repaired by freeing thebroken nerver ends, when the defect≥6cm, it can recover well by autologousnerve graft, which is currently the gold standard in clinical treatment. But thesupply source of autologous nerve used for autogenous nerve transplantationis limited, and it is inevitable course donor area loss of neurological function,partial sensory disturbance. In recent years nerve allograft transplantationbecome the focus of the study by scholars because of its wide raw materialsources, is similar in structure and easy to obtain. But the key problem is theadhesion and immune rejection, because the immune rejection of allogenicnerve failed to resolve, so there is no breakthrough progress in the clinicalapplication. How to reduce nerve allograft after transplantation inducedimmune rejection and the neural adhesion problem has been the biggestproblem in clinical application. Triptolide is an important active componentsof Chinese herb, which is anti-inflammatory, immune, antitumor. Amnioticmembrane is a semipermeable membrane,whose unique structure can preventmany substances throughing, can be wrapped in heterologous cells, tissue,intradural, and plays the role of mechanical barrier, can avoid immunerejection and amniotic membrane encapsulated nerve anastomosis, establisheda relatively closed space, reduce anastomotic adhesions around, to prevent theformation of scar tissue and reduce the loss of nerve growth factor for neuralrepair, and provide better microenvironment, enhance nerve repair effect.In this experimental rat sciatic nerve defect model was constructed, homologous nerve was transplantated, allograft gives people a fresh amnioticmembrane inclusions and give the triptolide, by gross observation, lightmicroscopy, scanning electron microscopy, flow cytometry detection, neuralelectrophysiological detection, sciatic nerve function index, three leg musclewet weight recovery rate analysis on the index, triptolide, human amnioticmembrane wrapped allogenic nerve to repair the peripheral nerve defects.Methods: Selection of weight200~250g80healthy SD rats, intersex,were randomly divided into A (Triptolide and amniotic membrane wrappedallogenic nerve group), B (nerve allograft group) in two groups, each groupof40. Two groups of animal are in the right thigh of exposure and removal ofa segment of the sciatic nerve (10mm), two sections of cutting the nerveanastomosis (exchange by10-0nylon suture for simple interrupted suture),preparation of nerve allograft model, group A nerve allograft with amnioticmembrane inclusions and supplemented by triptolide, B control group. After2,4and8weeks, gross observation, and respectively to damage far, proximaland middle2mm damage and2mm nerve segment, stained with HE, wereobserved under light microscope; after operation respectively2,4and8weeksof specimens, transmission electron microscope; respectively,7d,3D afteroperation14d and21d tail from the peripheral blood, do flow cytometrydetection of CD4, CD8and CD4/CD8; after8weeks of nerveelectrophysiological detection and three head muscle wet weight measurement;after4,8weeks of rat foot print analysis, calculate the sciatic functional indexand its recovery rate. All data were statistically processed.Results:1, gross observation:1.1,in two groups of rats after operation incision occurred12days afterinfection, incision suture removal, a healing period.1.2,2weeks after operation of lower limb slightly swollen, activity wassignificantly reduced and claudication, spirit is bad, eat less,2weeks after themental status and diet restored gradually.1.3,after2weeks of amniotic membrane localized slightly absorption,4week8weeks of absorption, completely absorbed. 1.4,group A allograft nerve and surrounding tissue adhesion and adhesionslightly loose, group B allograft nerve and surrounding tissue of extensive andclose adhesion, blunt and not easy to separate.2, light microscopic observation: after2,4,8weeks in the A group was higherthan that of group B nerve recovery.3,electron microscopy: after2weeks in the A group myelin hyperplasia, partof the plate structure is hierarchical, peeling phenomenon. Group B myelinobvious hyperplasia, lamellar-like structure fusion, obscure, microfilaments,microtubules was significantly reduced, part of myelin is statifiedphenomenon; after4weeks in the A group axonal slightly edema,mitochondria, microfilaments, microtubules and other organelles numbersgradually increased. B group is still obvious myelin swelling, lamellarstructure is not clear, separation, mitochondria, microfilaments, microtubulesand other organelles than in group A less. After8weeks in the A group ofmyelin is thin, smooth, clear lamellar structure, axonal mitochondrial,microfilaments, microtubules increased significantly and the morphologicalrules. Group B myelin visible mild hyperplasia, edema, axonal mitochondrialmicrofilaments, microtubules, slightly reduce the number of.4,flow cytometry detection: A, B in two groups of rats after the3D,7d,14d,28dCD4, CD8positive cell percentage and CD4/CD8comparison, the resultsshown in table (1,2,3,4). From table1we can see, after the3D, A group and Bgroup of mice peripheral blood CD4, CD8positive cell percentage and CD4/CD8ratio increased in statistical analysis, no significant difference; afterthe7d, A group and B group of mice peripheral blood CD4, CD8positive cellpercentage and CD4/CD8ratio were increased, but in B group increasedsignificantly, has statistically significant difference; the14d, A group and Bgroup of mice peripheral blood CD4, CD8positive cell percentage and CD4/CD8ratio was continues to increase, but in B group increased significantly,has statistically significant difference; the28d, A, B the two groups of miceperipheral blood CD4, CD8positive cell percentage and CD4/CD8ratiodrops relatively, has statistically significant difference. 5, the electrophysiological examination: after8weeks of neuralelectrophysiological testing results showed that, in B group than in A grouplong incubation period, slow nerve conduction velocities, low amplitude, hasstatistically significant difference (P <0.05)6, the sciatic function index: A group sciatic nerve function index recoveryrate was higher than that in group B, has statistically significant difference (P<0.01).7, after8weeks on the measured three head muscle wet weight recovery rate(three head muscle wet weight recovery rate=three head of lateral musclewet weight/normal sides three head muscle wet weight x100%) for statisticalanalysis, statistics showed significant difference.Conclusion:1, triptolide in allogeneic nerve to repair the peripheralnerve defect process has obvious promoting effect. The mechanism is asfollows: triptolide has excellent immunosuppressive and anti-inflammatoryeffects, it plays its immunosuppressive effects at the same time, no seriousdamage to the body's normal immune system monitoring function, do notcause serious infections. Can be considered as anti-rejection drugs in thetreatment of peripheral nerve allograft rejection is produced.2,fresh amniotic membrane can inhibit inflammatory reaction, relieve nerveinjury after hyperemia, edema and surrounding tissue adhesion;3, of fresh human amnion could inhibit the proliferation of fibrousconnective tissues, reduce nerve stump is scar formation, is conducive to theregenerating nerve growth and fiber bundle accurately to thereby improvingthe neurological recovery effect. |
PDF Full Text Request