黄芩、苍术对脾胃湿热证大鼠燥湿作用的性效关系

Property-efficacy Relationship of Scutellariae Radix and Atractylodis Rhizoma in Drying Dampness in Rats with Spleen-stomach Dampness-heat Syndrome

目的:观察黄芩和苍术对脾胃湿热证证候模型燥湿药效的差异,阐明黄芩和苍术燥湿作用的性效相关性。方法:64只雄性健康SD大鼠随机分为空白组,模型组,黄芩高、中、低剂量组,苍术高、中、低剂量组。通过内服高脂高糖饮食和外部湿热环境双重作用20 d复制脾胃湿热证模型。观察大鼠宏观表征;使用苏木素-伊红(HE)染色法,光镜下观察大鼠胃和结肠组织的形态学变化,并进行病理积分计算;采用酶联免疫吸附测定试验(ELISA)法检测大鼠血清中肿瘤坏死因子-α(TNF-α),白细胞介素-4(IL-4)和干扰素-γ(IFN-γ)含量;采用蛋白免疫印迹法(Western blot)检测大鼠胃组织水通道蛋白4(AQP4)蛋白含量表达;实时荧光定量聚合酶链式反应(Real-time PCR)法检测大鼠胃组织AQP4 mRNA表达。结果:与空白组比较,模型组大鼠宏观表征显示具有湿热证的表现;胃、结肠组织炎症反应明显,病理积分显著升高(P<0.01);血清中IFN-γ,IL-4和TNF-α含量升高(P<0.05);胃组织中AQP4蛋白和mRNA表达量呈升高趋势,但差异无统计学意义。与模型组比较,药物组大鼠宏观表征得到改善;黄芩对模型大鼠胃和结肠组织炎症具有明显的改善作用,苍术对模型大鼠结肠组织炎症有一定的改善作用,但对胃组织炎症改善作用不明显,黄芩各剂量组病理积分均有所降低,但在胃组织病理积分中,只有黄芩高剂量组差异有统计学意义(P<0.01),苍术各剂量组病理积分与模型组差异无统计学意义;在结肠病理积分中,除了苍术低剂量组无统计学意义,其他各用药组病理积分与模型组差异均有统计学意义(P<0.01)。黄芩和苍术各剂量组均能降低模型大鼠血清中IFN-γ,IL-4和TNF-α的含量(P<0.05,P<0.01);黄芩和苍术均能降低模型大鼠胃组织中AQP4蛋白表达量(P<0.01),黄芩高、低剂量组对模型组大鼠胃组织中AQP4 mRNA表达有降低的趋势,而黄芩中剂量组及苍术各剂量组对模型组大鼠胃组织中AQP4 mRNA表达有升高的趋势,但差异均无统计学意义。结论:黄芩和苍术对脾胃湿热证大鼠的燥湿作用具有一定的性效相关性,即其燥湿药效的强弱与其寒热药性有关,苦寒的黄芩比苦温的苍术作用效果更好。

Objective:To observe the difference in drying dampness between Scutellariae Radix and Atractylodis Rhizoma in model rats with spleen-stomach dampness-heat syndrome and clarify their propertyefficacy relationship.Method:Sixty-four healthy male SD rats were randomized into the blank group,model group,high-,medium-,and low-dose Scutellariae Radix groups,as well as high-,medium-,and low-dose Atractylodis Rhizoma groups.The rats were exposed to high-fat and high-sugar diet and external dampness-heat environment for 20 days for inducing the spleen-stomach dampness-heat syndrome.The macroscopic manifestations of rats were observed and the morphological changes in stomach and colon were detected under a light microscope after hematoxylin-eosin(HE)staining,followed by the calculation of pathological scores.The serum tumor necrosis factor-α(TNF-α),interleukin-4(IL-4),and interferon-γ(IFN-γ)levels were determined by enzyme-linked immunosorbent assay(ELISA).The protein and mRNA expression levels of aquaporin-4(AQP4)in the gastric tissue were measured by Western blot and Real-time polymerase chain reaction(Real-time PCR),respectively.Result:Rats in the model group presented with the manifestations of dampness-heat syndrome.The inflammatory reaction in stomach and colon was obvious,and the pathological score was significantly increased(P<0.01).The serum IFN-γ,IL-4,and TNF-αlevels were elevated(P<0.05),and so were the AQP4 protein and mRNA expression levels in the gastric tissue except that there was no statistical difference.The clinical symptoms of rats in the medication groups were alleviated.Scutellariae Radix significantly relieved the gastric and colonic inflammation in model rats.Atractylodis Rhizoma inhibited the colonic inflammation in model rats to a certain extent,but it had no obvious effect on gastric inflammation.The pathological score of each Scutellariae Radix group was decreased.In terms of the pathological score of gastric tissue,only the high-dose Scutellariae Radix produced a significant difference(P<0.01),and the pathological scores of the three Atractylodis Rhizoma groups were not significantly different from that in the model group.As for the pathological score of colonic tissue,all the medication groups except for the low-dose Atractylodis Rhizoma group exhibited a significant difference in comparison with that of the model group(P<0.01).Scutellariae Radix and Atractylodis Rhizoma at each dose reduced not only the serum IFN-γ,IL-4,and TNF-αlevels(P<0.05,P<0.01),but also the AQP4 protein expression in gastric tissue of model rats(P<0.01).The AQP4 mRNA expression in the gastric tissue of model rats declined in the high-and low-dose Scutellariae Radix groups,while that in the medium-dose Scutellariae Radix group and each Atractylodis Rhizoma group rose without statistical difference.Conclusion:Scutellariae Radix and Atractylodis Rhizoma display a certain property-efficacy relationship in drying dampness of rats with spleen-stomach dampness-heat syndrome.Specifically,the efficacy of drying dampness is related to their cold/heat property,and the resulting outcome of bitter-cold Scutellariae Radix is better than that of bitter-warm Atractylodis Rhizoma.