静脉内移植骨髓间充质干细胞在脑缺血大鼠脑内的分布及其对学习和记忆的影响

目的 观察骨髓间充质干细胞(bone mesenchymal stem cells,BMSCs)经静脉注射移植后在脑缺血大鼠脑内的存活和分布情况,以及对学习记忆的影响.方法 体外培养和扩增成年雄性SD大鼠BMSC,以"四管阻断法"制作大鼠前脑缺血再灌注模型,造模后3 d通过尾静脉注射Hoechst 33342标记的BMSC(2×106/ml),另设对照组通过尾静脉注射载体溶液,于注射后3周采用Morris水迷宫观察大鼠学习记忆功能,于注射后4周处死大鼠,取脑组织切片,于荧光显微镜下观察BMSC在脑内存活及分布情况.结果 BMSC移植大鼠逃避潜伏期、穿环次数和原象限时间与对照组相比有显著性差异(P＜0.05),其中,逃避潜伏期显著短于对照组,穿环次数和原象限时间显著高于对照组.结论 静脉注射移植BMSC能够进入大鼠脑内存活,主要分布在缺血性损伤部位,可改善脑缺血大鼠学习记忆能力.

Distribution of intravenously transplanted bone mesenchymal stem cells in ischemic brain and their effects on learning and memory in rats

Objective To investigate the distribution and migration of bone mesenchymal stem cells (BMSCs) in the brain after intravenous injection into brain-ischemic rats and to explore the effects on the learning and memory in rats. Methods Bone mesenchymal stem cells from adult rats were cultured in vitro. Then the cells were labeled by Hoechst 33342 and infused into the adult rats on day 3 after the ischemia/reperfusion model was established by cerebral artery occlusion. Morris water maze test was used to explore the effects on learning and memory function of the rats at 3 weeks after transplantation. Fluorescence microscope was used to identify BMSCs in rat brains at 4 weeks after transplantation. Results All indices in Morris water maze test were significantly different from those of control group at 3 weeks BMSCs transplantation(P<0.05). BMSCs survived and localized to the ipsilateral ischemic hemisphere. Conclusion BMSCs are able to survive and migrate to ischemic brain tissue through intravenous transplantation and improve the learning and memory function of rats.