Experimental Study Of Potential Repairment Of Rat Spinal Cord Injuries Using Activated Macrophages And Eripheral Nerve Transplantation

Objective:It's essential of axon regeneration in functional recovery after spinal cord injuries(SCI). But the regeneration was limited by the specific of CNS and the micro-enviroment after injuried. It was shown that the involvement of inflammatory cells,particularly macrophages which early and robust invade may improve the micro-enviroment of the injuried spinal cord and alleviate the secondary injury after SCI. And the eriphral nerve transplantation may provide channels and nutrition for axon regeneration. It may be a much more efficient way to stimulate the posttraumatic regeneration by transplanting macrophages and eripheral nerve together. Methods:We have grouped 222 Sprague Dawley rats in 7 groups randomly. Rats in group A were crushed injuried at semi-sected T10 level,group B were transplanted with actived macrophages which purified from abdominal,group C were semi-sected and cavitified at T10 level. In this cave,rats were grafted by active macrophages in group D,costal nerve in group E and both in group F. Rats in group G were supplement for other groups which rats were died during experiments. The physical improvement was evaluated by Basso,Beattie and Bresnahan locomotor rating scale (BBB scale). At various survival times such as 1,4 days and 1,2,4,6,8 weeks,spinal cords were fixed and cut into longitudinal or transversed frozen sections,and were immuneostained with antibodies EDI for activated macrophages,and NF for neurofilaments. Then the numbers of cells or neurofilaments were counted under microscope. Results:Activated macrophages have no rescue effect in crushed SCI. And the animal in this group have no restoration in hindlimb,less axons at injuried site. But transplantation with macrophages and eripheral nerve together showed improvement in hindlimb by BBB scale for 5-7 scores and decrease in cave of spinal cord that had caused by injuried . Significent myelinated axons regeneration in group F than in group D,E and C. Conclusion:Activated macrophages have different effect in crushed and semi-sected SCI,which have distinctive effect in the first group butpositive effect in the other. Transplantation with active macrophages and eriphral nerve is an effect way to reduce acute secondary injury and prove usefull therapy after spinal cord injuries.