The Study On Implantation Of Chitosan HydrOgel Containing BFGF And BDNF Into A Cortex Lesion Cavity Of The Rat Brain

Object To investigate the effect of hydrogel made from chitosan containing basic fibroblast growh factor(bFGF) and brain derived neurotrophic factor(bDNF) on inducing cellular migration, improving neural survival and promoting axonal regeneration after transplation into cerebral cortical injury site ,and study a treated measure in morphological reparing after the brain injury of the rat. Method The rat was placed in a stereotactic apparatus and the cerebral cortex of the brain was removed about 2×2×1.5mm .Chitosan containing bFGF and bDNF were implanted into the brain cortical lesion site of the rat imme- diately.Two to six months after hydrogel implantation into the lesioned cerebral cortex, The following stains were used: HE stain; immunohistochemistry used antibodies to glialfibrillary acidicprotein (GFAP), S-100 protein(S-100),OX42protein(OX42),CD68protein(CD68),neurofila mentprotein(NF);histochemistry: Sevier- Munger for nerve fiber and Marchall's silver for microglia. Result Chitosan hydrogel containing bFGF and bDNF were found within the cortical lesion site,forming a complete bridge between both sides of the lesion.Two month after transplantation new capillary were found within implatation. a large of astrocytes were found and astrocytes formed a scar tissue around the chitosan hydrogel.Meanwhile ,OX42+ and CD68+ cells were found in and out of implantation,and NF + neurons, NF + and silver impregnated axons were found around implantation.Four and six month after trans- plantation it results in a decrease in density of astrocyte around chitosan hydrogel, astrocyte migration,an increase of capillary and neural survival ,and an increase in NF+and silver impregnated axonal regeneration significantly, OX42+ and silver impregnated microglia were found in and out of the chitosan hydrogel. Conclusion The first,Chitosan hydrogel containing bFGF and bDNF was compatible with host tissue in central nervous system.The second,chitosan hydrogel could improve angiogenesis and induce gliocyte to migrate into it .The thirth, it improved neural survival and promote axonal regeneration. This hydrogel is a potention approach for treatement of brain injury.