穴位埋线对血管性痴呆大鼠学习记忆功能及海马微血管新生的影响

Effect of catgut implantation at acupoint on the learning and memory function and hippocampal microangiogenesis in vascular dementia rats

目的观察穴位埋线(CIAA)对血管性痴呆(VD)大鼠学习记忆功能、海马微血管新生情况以及促血管生成素1(Ang-1)/血管内皮生长因子(VEGF)及其受体TBK酪氨酸激酶(TIE2)/VEGF受体2(VEGFR2)mRNA和蛋白表达的影响,探讨穴位埋线预防和治疗VD的作用机制。方法采用随机数字表法将VD大鼠分为模型组、尼莫地平组和穴位埋线组,另设假手术组,各10只。术后第7天治疗组分别予以穴位埋线和尼莫地平灌胃治疗,治疗21 d后取材。Morris水迷宫行为学测试,HE染色观察海马CA1区组织,CD34免疫组织化学检测海马微血管密度(MVD),Real-time PCR和Western blotting检测海马Ang-1/VEGF及其受体TIE2/VEGFR2 mRNA和蛋白的表达。结果与模型组相比,其余各组平均逃避潜伏期明显缩短,目标象限停留时间明显延长(P<0.01,P<0.05)。与模型组相比,穴位埋线组和尼莫地平组海马CA1区可见核仁且形态饱满的锥体细胞数量均出现不同程度增多,且排列较紧密,仅少量细胞离散、肿胀。假手术组极少数CD34阳性细胞散在分布,治疗组CD34阳性分布较模型组紧密且染色明显;模型组MVD明显高于假手术组(P<0.01);尼莫地平组和穴位埋线组MVD均高于模型组(P<0.05,P<0.01)。与假手术组相比,模型组Ang-1/VEGF及其受体TIE2/VEGFR2 mRNA和蛋白的表达均明显增加(P<0.01,P<0.05);与模型组比,尼莫地平组和穴位埋线组上述因子mRNA和蛋白的表达均明显增加(P<0.01,P<0.05)。结论穴位埋线可改善VD大鼠学习记忆能力,促进海马微血管新生,其机制可能与Ang-1/VEGF及其受体TIE2/VEGFR2 mRNA和蛋白表达的上调有关。

Objective To observe the effect of catgut implantation at acupoint(CIAA)on the learning and memory function,hippocampal microangiogenesis,and the mRNA and protein expression of angiopoietin-1(Ang-1)/vascular endothelial growth factor(VEGF)and its receptor TEK tyrosine kinase(TIE2)/VEGF receptor 2(VEGFR2)in rats with vascular dementia(VD).To explore the mechanism of catgut implantation at acupoint in preventing and treating VD.Methods Using a random number table,VD rats were divided into a model group,a nimodipine group,and an catgut implantation at acupoint group,and a sham operation group was set up,with 10 rats in each group.On the 7th day after surgery,the treatment groups were given catgut implantation at acupoint and nimodipine gastric lavage for 21 days.After treatment,Morris water maze behavioral test was performed.HE staining was used to observe hippocampal CA1 tissue.CD34 immunohistochemical staining was used to detect hippocampal microvascular density(MVD).Real-time PCR and Western blotting were used to detect the mRNA and protein expression of Ang-1/VEGF and its receptor TIE2/VEGFR2 in the hippocampus.Results Compared with the model group,the average escape latency of the other groups was significantly shortened,and the target quadrant residence time was significantly prolonged(P<0.01,P<0.05).Compared with the model group,the number of nucleolus and well-formed pyramidal cells in hippocampal CA1 area of the catgut implantation at acupoint group and the nimodipine group increased in varying degrees,and they were arranged more closely,with only a few cells scattered and swollen.In the sham surgery group,a few CD34 positive cells were scattered.The treatment groups had more closely distributed CD34 positive cells with significant staining compared to the model group.The MVD of the model group was significantly higher than that of the sham surgery group(P<0.01).Both nimodipine group and catgut implantation at acupoint group had higher MVD than the model group(P<0.05,P<0.01).Compared with the sham surgery group,the mRNA and protein expression of Ang-1/VEGF and its receptor TIE2/VEGFR2 in the model group increased significantly(P<0.01,P<0.05).Compared with the model group,both nimodipine group and catgut implantation at acupoint group had higher mRNA and protein expression of Ang-1/VEGF and its receptor TIE2/VEGFR2(P<0.01,P<0.05).Conclusion Catgut implantation at acupoint can improve the learning and memory abilities in VD rats,promote hippocampal microvascular angiogenesis,which may be related to the up-regulation of Ang-1/VEGF and its receptor TIE2/VEGFR2 mRNA and protein expression.