RESUMO
Objective The extract of spinal cord tissue in morphine spared root rat was isolated and purified to look for some neurotrophic active substances. Methods Neurotrophic active substances were isolated and analysed by Sephacryl S 200 HR gel chromatography、high performance liquid chromatography(HPLC)and tissue culture,ect. Results The extract of spinal cord tissue of spared root rat could enhance the neurite growth of chick embryonal dorsal root ganglion(DRG) in vitro.There was also same effect in the extract of spinal cord tissue of morphine\|treated rat.But there was no significant difference in the extract of spinal cord tissue promoting the neurite growth between spared root rat and morphine treated rat.The extract of spinal cord tissue of morphine spared root rat had evident neurotrophic active role.The peak Ⅱ eluate and peak Ⅳ eluate obtained from the spinal cord tissue extract of morphine spared root rat through Sephacryl S 200 HR gel chromatography could promote the neurite growth of DRG.According to the analysis of SDS PAGE,the peak Ⅱ eluate showed one main protein zone with a molecular weight of 65kD and the protein composition of peak Ⅳ eluate was more complicated.The peak Ⅳ eluate of gel chromatography was then furhter isolated by HPLC.It was observed.That the peak A eluate of HPLC could promote the neurite growth of DRG. It was showed by SDS PAGE that the peak A eluate presented two main protein zones with molecular weight of 30kD and 18 kD.Conclusion\ The molecular weight of neurotrophic active substances,which were isolated from the extract of spinal cord tissue of morphine spared root rat,might be 65kD,30kD and 18kD proteins.\;[