补肾健脑方对血管性痴呆大鼠乙酰胆碱和海马区ERK1和ERK2表达的影响

Effects of Bushen Jiannao Recipe on the Content of Acetylocholine and the Hipppcampal ERK1 and ERK2 Protein Expressions of Vascular Dementia Rats

目的研究补肾健脑方对血管性痴呆(vascular dementia,VD)大鼠学习、记忆能力,皮质和海马乙酰胆碱(acetylcholine,ACh)含量,海马CA1区ERK1、ERK2阳性细胞表达的影响,并探讨其治疗VD的可能机制。方法选取83只大鼠,采用双侧颈总动脉永久结扎法(2-VO)制备VD动物模型。将造模组随机分为模型组、西药组及补肾健脑方高、中(各13只)、低(12只)剂量组。另选取13只大鼠作为假手术组。假手术组及模型组予蒸馏水灌胃(5mL/kg);西药组予盐酸多奈哌齐混悬液灌胃(0.52mg/kg);中药组予补肾健脑方组低(14g/kg)、中(28g/kg)、高(56g/kg)剂量灌胃;各组连续干预30天。采用Morris水迷宫实验测定大鼠逃避潜伏期及穿越平台数。比色法测定皮质、海马ACh含量,免疫组化法检测大鼠海马CA1区ERK1、ERK2阳性细胞表达数。结果用药组大鼠的平均逃避潜伏期总体呈逐渐下降趋势。与假手术组比较,模型组第3～5天逃避潜伏期延长,穿越平台数减少,皮质、海马ACh含量降低,海马CA1区ERK1、ERK2阳性细胞数减少,差异均有统计学意义(P<0.01)。与模型组比较,西药组及补肾健脑方高剂量组第4天逃避潜伏期均缩短,各用药组第5天逃避潜伏期均缩短,穿越平台数及海马CA1区ERK1、ERK2阳性细胞数增加,皮质ACh含量、海马ACh含量升高,差异均有统计学意义(P<0.05)。与补肾健脑方低剂量组比较,高剂量组第4、5天逃避潜伏期缩短,海马CA1区ERK1、ERK2阳性细胞数增加,差异有统计学意义(P<0.05)。与西药组比较,补肾健脑方低、中剂量组皮质、海马ACh含量降低(P<0.05)。结论补肾健脑方对VD模型大鼠的学习记忆功能减退具有改善作用,可能与提高皮质和海马ACh含量,促进海马CA1区ERK1、ERK2阳性神经元表达有关。

Objective To explore the effects of Bushen Jiannao Recipe（BJR） on the content of acetylocholine（Ach） and ERK1 and ERK2 protein expressions in the hipppcampal CA1 region of vascular dementia（VD） rats,and to explore its possible mechanisms for treating VD.Methods Eighty-three rats were selected.The VD model was established by permanent bilateral occlusion of both common carotid arteries（2-VO）.Then the modeled rats were randomly divided into 5 groups,i.e.,the memory deficit model group,the donepezil group,and the positive drug control groups [including high（n=13）,middle（n=13）,and low（n=12） dose BJR group].Besides,another 13 rats were chosen as the sham-operative group.The distilled water was given by gastrogavage to rats in the sham-operative group and the memory deficit model group（5 mL/kg）.The donepezil hydrochloride suspension was given to rats in the donepezil group by gastrogavage（0.52 mg/kg）.High（56 g/kg）,middle（28 g/kg）,and low（14 g/kg） dose of BJR were respectively given to rats in the other three groups.After 30 days of intervention,the escape latency period and platform crossing times were determined using Morris water maze experiment.The contents of Ach in the hippocampus and cortex were determined using colorimetry.The expressions of ERK1 and ERK2 in the CA1 region of the hippocampus were detected using immunohistochemical assay.Results The average escape latency of intervened rats showed an overall decreasing trend.From the third to the fifth day,the escape latency period was prolonged,the platform crossing times were reduced,the contents of Ach in the cortex and the hippocampus were lowered,the numbers of positive stained neuron of ERK1 and ERK2 in the hippocampus CA1 region were reduced,showing statistical difference when compared with the sham-operative group（P0.01）.Compared with the model group,the 4th day escape latency of the donepezil group and the high dose BJR group was shortened.The escape latency was shortened,and the platform crossing times,and the numbers of positive stained neuron of ERK1 and ERK2 in hippocampus CA1 region increased on the fifth day.The contents of Ach in the cortex and the hippocampus increased with statistical difference（P0.05）.Compared with the low dose BJR group,the 4th-and 5th-day latency period were shortened,the positive numbers of ERK1 and ERK2 in the hippocampus CA1 region increased in the high dose BJR group with statistical difference（P0.05）.Compared with the donepezil group,the Ach content in the cortex and the hippocampus of the middle and low dose BJR groups decreased（P0.05）.Conclusions BJR could obviously improve the function of learning and memory of VD rats.Its mechanisms might be associated with its actions in enhancing Ach contents of the cortex and the hippocampus,and promoting the protein expressions of ERK1 and ERK2 in the hippocampus CA1 region.