Experimental Study Of Mild Hypothermia And Neural Stem Cell Transplantation For Ischemic Nerve Dysfunction

In recent years the research of neural stem cells (NSCs) has become a hot point of the neuroscience studying realm. The stem cell technique such as separating, cultivation, purification and identification has already been opposite maturation in vitro. Our experiment has observed the therapeutical effect of those NSCs, which been transplanted into the brain of MCAO rat in condition of mild hypothermia. We study the survival, migration and integration of the neural stem cells into the cerebral arterial thrombosis rats` brain, and approach the channel, condition and time scale of stem cell transplantation for stroke patients.Objective: To explore the optimized condition and efficiency of neural stem cells (NSCs) transplantation for focal brain ischemia-reperfusion injury in rats.Methods: We separated neural stem cells from the cerebral cortex of SD rats'embryos and cultured in condition with combination of bFGF,EGF,N2 and B27, then purified NSCs and identified them by immumofluorescence method. The primary cultured fetal brain neural stem cells which been labeled with BrdU 3 days before transplantation were transplanted into the ischemic cortex of MCAO rats. 35 days later, behavioral test and Zeal Longa's method were used to evaluate the neural function deficits. One day before it, brains were removed then the BrdU,NeuN and GFAP were detected by method of immunohistochemistry.Results: The neural stem cells with the abilities of self-renewal and multipotency were successfully isolated and cultured from 13.5-days embryonic rats` cerebral cortex. A combinative nutritive medium within bFGF,EGF,N2 and B27 could be used to expand rats'neural stem cells for long time, in order to get enough cells for transplantation. Those NSCs were identified by immumofluorescence method of Nestin,GFAP and NeuN. The MCAO model could be successfully reproduced, and 35-days later from transplanting action, the significant deviation of NSS between positive control group and mild hypothermia experiment group could be observed. There was a distinctive improving be observed between two groups. BrdU-positive cells could be detected in the animal brain, nestin down-regulation and multipotency in vivo were observed and NeuN-positive cells were detected.Conclusion: By using the combinative nutritive medium within bFGF,EGF,N2 and B27, NSCs could be isolated and cultured from 13.5-days embryonic rats. We could make up higher achievement ratio and better reproducibility MCAO rats'models. Those NSCs which were transplanted into the cerebral ischemia focus could survival and differentiate. The transplanting effective in condition of mild hypothermia is better than in simple, no matter in praxiology or in histology.