吡拉西坦联合盐酸多奈哌齐对阿尔茨海默病大鼠海马区小胶质细胞活化的影响

Effect of piracetam combined with donepezil hydrochloride on the activation of microglia in the hippocampus of Alzheimer’s disease rats

目的探讨吡拉西坦(PT)联合盐酸多奈哌齐(DH)对阿尔茨海默病(AD)大鼠海马区小胶质细胞活化的影响。方法双侧海马注射凝聚状态Aβ1-42法建立AD模型。50只大鼠按照体质量随机分为假手术组、模型组、对照A组、对照B组和实验组,每组10只。除假手术组外,其余4组建立AD大鼠模型。模型制备成功后,开始给药。对照A组灌胃给予0.3 g·kg^(-1)PT;对照B组灌胃给予5.0 mg·kg^(-1)DH;实验组灌胃给予0.3 g·kg^(-1)PT+5.0 mg·kg^(-1)DH;假手术组和模型组均灌胃给予等量0.9%Na Cl。5组大鼠每天给药1次,连续给药21 d。用Morris水迷宫检测认知功能,用免疫组织化学法检测海马组织中离子钙接头蛋白1(Iba-1)的表达情况,用免疫荧光法检测海马组织中CD11b和胶原纤维酸性蛋白(GFAP)的表达情况。结果给药21 d后,实验组、对照A组、对照B组、模型组和假手术组的目标象限停留时间分别为(37.42±3.56),(20.34±3.80),(21.19±3.28),(15.36±3.67)和(45.40±4.22) s,穿越平台次数分别为(4.58±0.70),(3.25±0.61),(3.31±0.64),(2.04±0.62)和(7.21±0.95)次,海马组织中Iba-1蛋白平均光密度值分别为2.91±0.50,4.04±0.60,4.10±0.61,7.26±0.75和0.51±0.12,CD11b荧光强度分别为31.86±3.79,50.30±4.86,51.62±4.01,72.54±4.21和9.71±2.50,GFAP荧光强度分别为37.58±4.16,54.12±5.45,55.19±5.80,93.04±7.26和14.45±4.73,实验组、对照A组和对照B组的上述指标与模型组比较,差异均有统计学意义(均P<0.05)。结论 PT联合DH可有效地改善AD大鼠认知功能,抑制海马区小胶质细胞活化。

Objective To investigate the effect of piracetam (PT)combined with donepezil (DH) on the activation of microglia in the hippocampus of Alzheimer’s disease (AD) rats.Methods The AD model was established by bilateral hippocampus injection of condensed state Aβ1-42.Fifty rats were randomly divided into sham-operation,model,control A,control B and experimental groups according to body weight,with 10 rats per group.Except for the sham-operation group,the AD rat models were established in the other 4 groups.After the model was successfully prepared,the drug was administrated.The control A group was given 0.3 g·kg^(-1)PT,the control B group was given 5.0mg·kg^(-1)DH,and the experimental group was given 0.3 g·kg^(-1)PT+5.0 mg·kg^(-1)DH,the sham-operation and model groups were given the same amount of 0.9%NaCl.Five groups were administered by gavage once a day for 21 consecutive days.The rat’s cognitive function was tested by Morris water maze test.The expression of ionized calcium bindingadaptor molecule-1 (Iba-1) in the hippocampus was detected by immunohistochemistry.CD11b and glial fibrillary acidic protein (GFAP) in the hippocampus were detected by immunofluorescence.Results After 21 days of administration,the target quadrant residence time of experimental,control A,control B,model and sham-operation groups was (37.42±3.56),(20.34±3.80),(21.19±3.28),(15.36±3.67) and (45.40±4.22) s,the number of crossing platforms was (4.58±0.70),(3.25±0.61),(3.31±0.64),(2.04±0.62) and (7.21±0.95) times,the average optical density values of Iba-1 protein in hippocampus were 2.91±0.50,4.04±0.60,4.10±0.61,7.26±0.75 and 0.51±0.12,the fluorescence intensities of CD11b were 31.86±3.79,50.30±4.86,51.62±4.01,72.54±4.21 and 9.71±2.50,the GFAP fluorescence intensities were 37.58±4.16,54.12±5.45,55.19±5.80,93.04±7.26 and 14.45±4.73.The above indexes of experimental,control A and control B groups were compared with model group,and the differences were statistically significant (all P<0.05).Conclusion PT combined with DH can effectively improve the cognitive function of AD rats and inhibit the activation of microglia in the hippocampus.