嗅三针对血管性痴呆大鼠学习记忆功能及海马生长抑素、精氨酸加压素含量的影响

摘要

目的:观察嗅三针对血管性痴呆(vascular dementia,VD)大鼠学习记忆功能及海马神经肽的影响,探讨嗅三针治疗VD的作用机制.方法:成年SD雄性大鼠40只,随机分为正常组、VD模型组、VD嗅球损毁针刺组、嗅三针组,每组10只.四血管阻断法制作VD大鼠模型,电凝法损毁嗅球模型.电针双侧"迎香""印堂",每日1次,共6周,水迷宫测试大鼠学习记忆能力,放射免疫法测定海马神经肽生长抑素(soma-tostatin,SS)和精氨酸加压素(arginine vasopressin,AVP)含量.结果:定位航行试验显示:平均逃避潜伏期比较,VD模型组长于正常组(P＜0.01);嗅三针组短于VD模型组及VD嗅球损毁针刺组(P＜0.01);VD嗅球损毁针刺组与VD模型组比较差异无统计学意义(P＞0.05).空间探索试验显示:原平台象限跨越相应平台的次数比较,VD模型组少于正常组(P＜0.01);嗅三针组多于VD模型组及VD嗅球损毁针刺组(P＜0.01);VD模型组与VD嗅球损毁针刺组比较差异无统计学意义(P＞0.05).海马 SS、AVP含量比较,VD模型组低于正常组(P＜0.05);嗅三针组高于VD模型组及VD嗅球损毁针刺组(P＜0.05);VD模型组与VD嗅球损毁针刺组比较差异无统计学意义(P＞0.05).结论:嗅三针能够增强VD大鼠学习记忆功能,并且能提高海马神经肽SS、AVP的含量,其治疗效应的发挥与嗅觉传导通路的完整性有关.%Objective To observe the effect of electroacupuncture (EA) of "Xiusanzhen" [bilateral "Yingxiang" (LI 20) + "Yintang" (GV 29)] on learning-memory ability and hippocampal somatostatin (SS)and arginine vasopressin (AVP) contents in vascular dementia (VD) rats. Methods Forty SD rats were randomly divided into control, VD model, VD plus olfactory bulb lesion (OBL, destroyed by electro-coagulation) and EA groups, with 10 cases in each. VD model was established by 4-vessel occlusion. Morris maze tests were conducted for evaluating the rats' learning and memory ability. EA (1-3 mA, 80/100 Hz) was applied to bilateral LI 20 and GV 29 in VD+ OBL and EA groups for 10 min, once daily (except Saturdays and Sundays) for 6 weeks. The contents of SS and AVP in hippocampus tissue were measured by radioimmunoassay. Results In comparison with control group, the average escape latency (AEL) prolonged significantly and the target-platform crossing times (TPCT) decreased remarkably in VD model group (P<0. 01). In comparison with VD model group, the AEL was shortened and TPCT increased remarkably in EA group (P<0. 01). No significant differences were found between VD model and VD + OBL groups in the AEL and the TPCT (P>0. 05). Hippocampal SS and AVP contents in VD model group were significantly lower than those in control group (P<0.05), while those in EA group were markedly higher than those in VD model group (P<0. 05). No significant differences were found between VD model and VD + OBL groups in SS and AVP contents (P>0. 05). Conclusion EA of "Xiusanzhen" can improve VD rats' learning-memory ability, which may be related to its effects in raising hippocampal SS and AVP contents and to the intact olfactory pathway.