The Impact Of Local Mild Hypothermia On Endougenous Neural Stem Cells In Different Rat Models Of Stroke

Objective:Ischemic stroke can induce the increase of endogenous neural stem cells to repair injure, however this kind of change is thought to be limited. Hypothermia therapy is one of the neuroprotective methods. We planed to observe the impact of Hypothermia therapy on the proliferation of endogenous neural stem cells in different ischemic models.Methods:108SD rats were divided into five groups, sham group, tMACO group, pMACO group, tMACO+Hypothermia group and the pMACO+hypothermia one. Then the five groups were subdivided into6h,2d and7d groups according to the ischemia time. Brdu and nestin were used to mark the proliferative neural stem cells.Results:Neurological deficit score declined with the time extending. There was no difference of infarct volume among four experimental groups. Brdu and nestin positive cells were observed in the the subgranular zone (SGZ) of the hippocampus and cortex, increased at6hours after MACO and reached the peak at7days. Nestin positive cells in cortex increased significantly in the hypothermia group.Conclusion:Cerebral ischemia could stimulate neurogenesis in adult brain. Transient mild hypothermia therapy may strengthen migration of stem cells to injure zone, hypothermia combined with reperfusion has a greater brain protective effect than non-reperfusion one in a short period.12Figures,7Tables,53References.