“百会”“大椎”穴电针预处理减轻反复丙泊酚麻醉诱导的大鼠学习记忆障碍

Electro-Acupuncture Preconditioning at DU20 and DU14 Attenuating Learning and Memory Impairment Induced by Repeated Propofol Anesthesia in Rats

目的:观察“百会”“大椎”穴电针预处理减轻反复丙泊酚麻醉诱发大鼠学习记忆障碍的作用。方法:通过给予连续5 d丙泊酚麻醉诱导学习记忆障碍模型,在丙泊酚给药前给予电针预处理连续5 d完成电针干预。Morris水迷宫检测大鼠学习记忆能力;HE染色用于观察海马神经细胞数量及形态改变;免疫荧光染色检测海马Dentate Gyrus区磷酸化环磷腺苷效应元件结合蛋白(pCREB)蛋白表达;用Western Blotting测定B细胞淋巴瘤-2(Bcl-2)、半胱氨酸蛋白酶-3(Caspase-3)、B细胞淋巴瘤-2相关X蛋白(Bax)和CREB蛋白的表达情况。结果:Morris水迷宫结果:与对照组比较,丙泊酚组大鼠的穿台次数、目标象限游泳时长及路径占比明显减少,差异具有统计学意义(P<0.05);电针组大鼠的穿台次数、目标象限游泳时长及路径占比均明显高于丙泊酚组,差异具有统计学意义(P<0.05)。HE结果:丙泊酚组海马DG区细胞层数减少,细胞密集度降低;电针组海马DG区神经元细胞层数显著恢复,细胞密集度明显升高。免疫荧光结果:与对照组比较,丙泊酚组海马区pCREB蛋白累积荧光强度显著降低,差异具有统计学意义(P<0.05);与丙泊酚组比较,电针组海马区pCREB蛋白累积荧光强度显著升高,差异具有统计学意义(P<0.05)。Western blot结果:与对照组比较,Bax、Caspase-3在丙泊酚组显著表达,差异具有统计学意义(P<0.05),而Bcl-2、CREB表达明显减少,差异具有统计学意义(P<0.05);与丙泊酚组比较,Bax、Caspase-3在电针组表达明显减少,差异具有统计学意义(P<0.05),相反,Bcl-2、CREB在电针组显著表达,差异具有统计学意义(P<0.05)。结论:“百会”“大椎”穴电针预处理可以有效减轻反复丙泊酚麻醉诱发的大鼠学习记忆障碍,其机制可能与上调pCREB、CREB蛋白以及调控凋亡相关因子的表达,进而抑制神经元凋亡,改善学习记忆,发挥神经保护作用。

Objective:To observe the effect of electro-acupuncture(EA)preconditioning at Baihui(DU20)and Dazhui(DU14)on reducing learning memory impairment induced by repeated propofol anesthesia in rats.Methods:The model of learning and memory impairment was induced by 5 consecutive days of propofol anesthesia,and EA pretreatment was given for 5 consecutive days before propofol administration.The learning and memory ability was evaluated by Morris water maze.The amount and morphological change of hippocampal neurons were observed by HE staining.The protein expression of pCREB in the Dentate Gyrus region of hippocampus was measured by immunofluorescence staining.The protein expressions of Bcl-2,Caspase-3,Bax and CREB were determined by Western Blotting.Results:In terms of Morris water maze results,compared with those in the control group,the number of platform crossing,the swimming time and the percentage of paths in the target quadrant were significantly reduced in the propofol group(P<0.05);compared with those in the propofol group,the number of platform crossing,the swimming time and the percentage of paths in the target quadrant were significantly increased in the EA group(P<0.05).In terms of the HE results,compared with those in the control group,the number of cell layers in the hippocampal DG area decreased and the cell density decreased in the propofol group;compared with those in the propofol group,the number of neuronal cell layers in the hippocampal DG area significantly recovered and the cell density significantly increased in the EA group.In terms of the immunofluorescence results,compared with that in the control group,the intergrated fluorescence intensity of pCREB protein in the hippocampal region was significantly reduced in the propofol group(P<0.05);compared with that in the propofol group,the intergrated fluorescence intensity of pCREB protein in the hippocampal region was significantly increased in the EA group(P<0.05).In terms of the Western Blotting results,compared with those in the control group,the expressions of Bax and Caspase-3 were significantly increased(P<0.05),whereas the expressions of Bcl-2 and CREB were significantly decreased in the propofol group(P<0.05);compared with those in the propofol group,the expressions of Bax and Caspase-3 were significantly decreased(P<0.05),and the expressions of Bcl-2 and CREB were significantly increased in the EA group(P<0.05).Conclusion:Electro-needling DU20 and DU14 can effectively reduce learning and memory impairment induced by repeated propofol anesthesia in rats,and the mechanism may be related to up-regulating the proteins of pCREB and CREB and the expression of apoptosis-related factors,which in turn inhibits neuronal apoptosis,improves learning and memory ability,and exerts neuroprotective effects.