愈癫汤对精神分裂症模型大鼠脑组织Glu/GABA代谢平衡的影响

Effects of Yudian Decoction(愈癫汤)on the Metabolic Balance of Glu/GABA in the Brain Tissue of Schizophrenia Model Rats

目的探讨愈癫汤治疗精神分裂症的可能作用机制。方法5只正常雌性孕17天SD大鼠所产雄性子鼠选取20只为空白组。15只雌性孕17天SD大鼠单次性腹腔注射醋酸甲基偶氮甲酯(MAM)25 mg/kg,所产雄性子鼠模拟神经发育异常建立精神分裂症大鼠模型。选取造模成功60只子鼠随机分为模型组、愈癫汤组、利培酮组各20只。适应性分笼喂养3天后,愈癫汤组大鼠灌胃愈癫汤1.54 g/(kg·d),利培酮组灌胃利培酮胶囊0.24 mg/(kg·d),空白组和模型组灌胃6.7 ml/(kg·d)蒸馏水,每日灌胃1次,连续14天,最后一次灌胃后次日取材。免疫荧光法检测海马区和前额叶皮质中谷氨酸受体(GluR)、γ-氨基丁酸受体亚单位α1(GABAARα1)阳性神经元的表达情况,计算阳性率;免疫组织化学法检测海马CA1区和内侧前额叶皮质中小清蛋白(PV)表达;蛋白免疫印迹法和反转录PCR法检测海马区和前额叶皮质中谷氨酸脱羧酶65(GAD65)、谷氨酸脱羧酶67(GAD67)蛋白及mRNA表达。结果与空白组比较,模型组大鼠海马区和前额叶皮质GluR阳性率升高,海马区GABAARα1阳性率降低,海马CA1区和内侧前额叶皮质中PV光密度值均降低,海马区和前额叶皮质中GAD65、GAD67蛋白及mRNA表达均降低(P<0.05或P<0.01)。与模型组比较,利培酮组、愈癫汤组海马区和前额叶皮质中GluR阳性率均降低,海马区GABAARα1阳性率均升高,海马CA1区和内侧前额叶皮质中PV光密度值均升高,海马区和前额叶皮质中GAD65、GAD67蛋白及mRNA表达均升高(P<0.05或P<0.01)。与利培酮组比较,愈癫汤组海马区和前额叶皮质中GluR、海马区GABAARα1阳性率均降低,海马CA1区PV光密度值升高,海马区GAD67蛋白及mRNA表达升高,前额叶皮质中GAD65蛋白表达降低(P<0.05)。结论愈癫汤可能通过调节海马区及前额叶皮质谷氨酸/γ-氨基丁酸(Glu/GABA)代谢平衡的关键调控因子,维持大脑神经元兴奋和抑制之间的平衡状态,从而改善精神分裂症的病理过程。

Objective To explore the possible mechanism of Yudian Decoction(愈癫汤)in the treatment of schizophrenia.Method Twenty male offspring from 5 normal female 17-day-pregnant SD rats were selected as blank group.Fifteen female 17-day-pregnant SD rats were injected intraperitoneally with methyl azomethine acetate(MAM)25 mg/kg,and the male offspring simulated the neurodevelopmental abnormality to establish a rat model of schizophrenia.Sixty successfully-modeled rats were randomly divided into 20 rats in the model group,20 rats in the Yudian Decoction group and 20 risperidone group.After 3 days of adaptive cage feeding,the rats in the Yudian Decoction group were gavaged with 1.54 g/(kg·d)of Yudian Decoction,the risperidone group was gavaged with 0.24 mg/(kg·d)of risperidone capsule,while the blank group and the model group were gavaged with 6.7 ml/(kg·d)of distilled water,once a day,for 14 consecutive days.Sample was collected on the day after the last gavage.The expression of glu⁃tamate receptor(GluR)andγ-aminobutyric acid receptor subunitα1(GABAARα1)-positive neurons in the hippocam⁃pus and prefrontal cortex were detected by immunofluorescence,and the positive rate was calculated;the expression of small clear proteins(PVs)in the hippocampal CA1 region and the medial prefrontal cortex was detected by immu⁃nohistochemistry;The expression of glutamic acid decarboxylase 65(GAD65)and glutamic acid decarboxylase 67(GAD67)proteins and mRNAs in the hippocampus and prefrontal cortex were detected by immunoblotting and re⁃verse transcription PCR.Result Compared with the blank group,the positive rate of GluR in hippocampal area and prefrontal cortex of rats in the model group increased,the positive rate of GABAARα1 in hippocampal area de⁃creased,the PV optical density value in hippocampal CA1 area and medial prefrontal cortex decreased,and the expression of GAD65,GAD67 proteins and mRNA in hippocampal area and prefrontal cortex decreased(P<0.05 or P<0.01).Compared with the model group,GluR positivity rate in hippocampus and prefrontal cortex of risperidone group and Yudian Decoction decreased,GABAARα1 positivity rate in hippocampus increased,PV optical density value in hippocampus CA1 area and medial prefrontal cortex increased,and GAD65,GAD67 proteins and mRNA expression in hippocampus and prefrontal cortex increased(P<0.05 or P<0.01).Compared with the risperidone group,the positive rate of GluR in hippocampus and prefrontal cortex and GABAARα1 in hippocampus in the Yudian Decoction group was reduced,the PV optical density value of hippocampal CA1 area was increased,the protein and mRNA expression of GAD67 in hippocampus area was elevated,and the protein expression of GAD65 in prefrontal cortex was reduced(P<0.05).Conclusion Yudian Decoction may improve the pathological process of schizophrenia by regulating key regulators of glutamate/γ-aminobutyric acid(Glu/GABA)metabolic balance in the hippocampus and prefrontal cortex and maintaining the balance between neuronal excitation and inhibition.