ABSTRACT
Objectives To observe the effects of electroacupuncture (EA) treatment of different intensities on learning-memory function and expression of β-amyloid protein 1-40 (Aβ1-40) in hippocampus CA1 region in rats with vascular dementia (VD) and to seek the best intensity of EA treatment.Methods A total of 60 male SD rats (SPF grade) were enrolled.Eight rats were selected as sham operation group with random number table method;others were used to copy the VD model with the modified four-vessel occlusion (4-VO) method.According to the random number table method,the successful model of the rats (n=24) were completely randomly divided into a model group,a 1 am EA group (frequency,2/15 Hz,intensity,1 mA,needle retention time,20 min),and a 3 mA EA group (frequency,2/15 Hz,intensity,3 mA,needle retention time,20 min;n=8 in each group).DU20 (BaiHui) and DU14 (DaZhui) in the EA group were acupunctured once a day for 10 d,and took a rest for 2 d as 1 treatment course.After 2 treatment courses,Morris water maze test was used to detect the ability of learning and memory of rats in each group.Fluorescent quantitative polymerase chain reaction was used to detect the expression level of Aβ1-40 mRNA.Results The mean escape latencies of the water maze test from 2 to 5 days in the sham operation group,model group,1 mA EA group,and 3 mA EA group were 46.8±1.9,40.6±2.3,24.6±1.5,19.4 ±1.2 s;56.3±3.5,51.2±2.6,45.9±2.1,40.8±1.4 s,52.7±1.5,46.0±2.3,31.3±1.2,27.7±1.6 s;and 50.8±3.9,41.5±2.1,29.0±1.1,25.6±1.3 s,respectively;the first time across the original platform were 23.3±1.6,53.9±1.3,30.2±1.4,and 28.1±0.8 s,respectively;the first across the original platform within 120 s were 9.4±0.9,2.6±0.5,6.4±0.7,and 7.2±0.9,respectively;the expression levels of Aβ 1-40 mRNAs in the CA1 regions were 17.3±1.1,40.7±1.1,24.0±1.7,and 22.4±1.8,respectively.There were significant differences among the groups (the F values were 195.88,861.605,103.876,and 380.609,respectively;all P<0.01).Compared with the model group,the mean escape latencies,the first time across the original platform were reduced significantly.Compared with the model group,the times across the original platform within 120 s were increased significantly.Compared with the model group,the gene expression level of Aβ 1-40 mRNA in the center of CA1 region was decreased significantly,and the 3 mA EA group was significantly superior to that of the 1 mA EA group.The difference was statistically significant (all P<0.05).Conclusion EA may improve the learning and memory ability in VD rats and lower the expression level of Aβ 1-40 mRNA in the CA1 region of hippocampus.Effect of 3 mA EA is better than that of the 1 mA EA.