脐血单核细胞对VD大鼠认知功能及脑组织BDNF的影响

Effects of intracarotid administration of human cord blood mononuclear cells on cognitive functions and content of brain-derived neurotrophic factor in the vascular dementia rats

目的观察颈内动脉输注脐血单核细胞(Human cord blood mononuclear cells,HCMNCs)对血管性痴呆(Vascular dementia,VD)大鼠认知功能及脑组织脑源性神经营养因子(Brain-derivedneurotrophicfactor,BDNF)含量的影响。方法改良Pulsinellis四血管阻断法建立VD大鼠模型;体外分离HCMNCs,术后24h颈内动脉输注数量为3×106/0.5ml的BrdU标记细胞;利用穿梭箱系统和ELISA法检测注射HCMNCs后2、4、8周VD大鼠学习记忆能力以及脑组织BDNF含量的变化。结果模型组大鼠主动回避反应比率明显低于对照组(P<0.01),治疗组较模型组显著提高(P<0.01)。术后2周模型组大鼠脑组织BDNF含量较对照组明显增高(P<0.01),4周时达到高峰(P<0.01),8周时则明显下降,与2周时相比有显著性差异(P<0.05);颈内动脉输注HCMNCs后治疗组大鼠脑组织BDNF含量较模型组显著升高(P<0.01),4周时最高(P<0.01),8周时略有下降,但仍维持在较高水平,与4周时相比无显著性差异(P>0.05)。结论颈内动脉输注HCMNCs可显著改善VD大鼠学习记忆能力,增加VD大鼠脑组织BDNF含量,具有脑保护作用。

Objective To explore the effects of intracarotid administration of human cord blood mononuclear cells （HCMNCs） on cognitive functions and content of brain-derived neurotrophic factor （BDNF） in the vascular dementia （VD） rats. Methods The VD rat model was established by modified pulsinellis 4-vessel occlusion （4 VO）. HCMNCs were isolated from human umbilical cord blood in vitro. The treatment group received intracarotid infusion 3×10^6/0.5 ml HCMNCs which were prelabeled with BrdU in vitro.The learning-memory abilities and the contents of BDNF were observed on the 2nd w,4th w and 8th w by computerized shuttle-training case and Enzyme-linked immunoadsordent assay（ELISA）. Results AAR ratio in the model group showed significantly decrease compared with the control（P〈0.01）, and the treatment group was significant higher than the model group （P〈0.01）. The contents of BDNF in the model group was significantly higher than that in the control group,increased to the highest level on the 4th w, and then decreased on the 8th w but compared with that on the 2th w, significant difference was found.Compared with the model group, the contents of BDNF in the treatment group showed significantly increase after infusion of HCMNCs, increased to the highest level on the 4th w, and then decreased on the 8th w but maintained the high level, there were no significant difference between that on the 4th w and on the 8th w.Conclusion Intracarotid administration of HCMNCs could significantly improve the learning-memory abilities and increased the contents of BDNF in the VD rats.