针刺对拟血管性痴呆大鼠脑内NO、NOS及血液流变学影响的实验研究

目的:建立拟血管性痴呆(VD)的动物模型,探讨针刺对VD大鼠模型的学习记忆行为、脑内NO含量、NOS活性及VD大鼠血液流变学的影响。方法:选用纯系健康雄性Wistar大鼠36只,随机分成假手术组、模型组、针刺组和西药对照组,采用2-血管阻断法(2-VO)制作VD大鼠模型。在大鼠“百会”“大椎”穴行针刺治疗。检测VD大鼠穿梭箱实验成绩,比色法检测脑组织NO含量、NOS活性,并检测VD大鼠的全血粘度、血浆粘度、红细胞压积及纤维蛋白原浓度。结果:数据经统计学处理表明,针刺“百会”“大椎”穴可明显减少模型大鼠在穿梭箱实验中的电击次数和电击时间(P<0.01);降低脑组织内NO的含量及NOS活性(P<0.05);可使VD大鼠的全血粘度、血浆粘度、红细胞压积及纤维蛋白原浓度降低(P<0.05,0.01)。结论:针刺能改善VD大鼠的学习记忆能力,降低脑组织内NO的含量及NOS活性,改善VD大鼠的血液流变学状态,从而改善大脑的血液供应,促进智能的恢复。

Effect of Acupuncture on Cerebral NO Content and NOS Activity and Hemorheology in Vascular Dementia Rats

Objective: To observe the effect of acupuncture on hemorheology and cerebral nitric oxide synthase(NOS) activity and nitric oxide(NO) content in vascular dementia(VD) rats.Methods: A total of 36 Wistar rats were evenly and randomly divided into control,model,acupuncture and medication groups.VD model was established by using 2-vascular occlusion method."Baihui"(GV 20) and "Dazhui"(GV 14) were punctured with the needles manipulated for 5 min and retained for 30 min,once daily,4 weeks altogether.Rats of medication group were fed with Piracotum(20 mg/mL),once daily,4 weeks altogether.The rats' learning and memory ability was tested by using shuttle box(passive and active avoidance) test.At the end of the study,blood samples were collected by extracting out the eyeball for detecting whole blood viscosity(WBV),plasma viscosity(PV),hematocrit and fibrinogen content separately,and the brain tissues(except brainstem and cerebella) were taken out to be processed into homogenate for detecting NOS activity and NO content with colorimetric method.Results: Before operation,there were no significant differences among the 4 groups in the times and duration of electric shock,and after operation,the electric shock times and duration of model group increased significantly compared with control group(P<0.05) and with pre-operation in the same group(P<0.001).Compared with model group, the electric shock times and duration of acupuncture and medication groups decreased considerably after operation(P<0.01),suggesting an improvement of the VD rats' learning-memory ability.In comparison with control group,cerebral NO content and NOS activity increased markedly(P<0.001),and compared with model group,these two indexes of acupuncture and medication groups lowered significantly(P<0.05) in spite of being higher than those of control group(P<0.05).No significant differences were found between acupuncture and medication groups in the abovementioned 4 indexes(P>0.05).Compared with control group,the values of high,medium and lower shear rates,PV,hematocrit and fibrinogen in model group were all markedly higher(P<0.05,0.001),while in comparison with model group,these six indexes of acupuncture group declines significantly(P<0.05,0.01) despite of being significantly higher than those of control group(P<0.05).No significant differences were found between medication and model group in the aforementioned six indexes of hemorheology(P>0.05).It indicated that acupuncture could improve hemorheology in VD rats,while medication had no significant effect.Conclusion: Acupuncture of GV 20 and GV 14 can improve the learning and memory ability,reduce cerebral NOS activity and NO content,and improve hemorheology in VD rats.