基于风寒表证大鼠的麻黄升浮药性研究

Study on the ascending and floating medicinal properties of Ephedra based on wind-cold exteriorpattern rat

目的:探讨麻黄水提物对风寒表证大鼠中枢系统、呼吸系统、泌尿-发汗系统、循环系统及消化系统的干预作用,阐明麻黄升浮药性的科学内涵。方法:风扇吹风加寒冷刺激的方法构建风寒表证动物模型,大鼠出现喷嚏、流涕、聚卧蜷缩状并且体温升高则表明造模成功,造模成功后将大鼠分为模型组,对乙酰氨基酚(0.455g/kg)组,麻黄低、中、高剂量(1.170、2.340、4.680g/kg)组。连续灌胃给药4d后,观察大鼠的一般状况,并检测大鼠中枢系统指标[体温,活动距离,睡眠时间,血清中白介素-4(IL-4)、γ-干扰素(IFN-γ)水平]、呼吸系统指标(氨水诱咳实验、酚红排泌量)、泌尿-发汗系统指标[汗腺切片、汗液分泌量、尿量及血中肌酐(CRE)、尿素氮(BUN)水平]、循环系统指标[心功能及血清一氧化氮(NO)水平]、消化系统指标[胃残留率、胃排空速率、小肠推进率及血浆胃动素(MTL)、胃泌素(GT)及生长抑素(SST)水平],并对这五大系统各指标进行关联性分析来综合评价麻黄的升浮药性。结果:麻黄中剂量(2.340g/kg)是改善风寒表证模型的最佳剂量。麻黄的“升浮”药性体现在其改善风寒表证大鼠的体温、活动距离、睡眠时间(P<0.05,P<0.01)来发挥兴奋中枢的作用;延长风寒表证大鼠咳嗽潜伏期、减少咳嗽次数(P<0.05,P<0.01)以宣发肺气;增加模型大鼠的发汗量及尿量(P<0.05,P<0.01)来发表散寒;但对循环系统无显著影响。麻黄水提物高剂量对消化系统的促进作用(P<0.01)可能与其不良反应有关。结论:麻黄的“升浮”药性体现在对风寒表证模型的“宣发”和“发散”上。

Objective: To explore the effects of Ephedra aqueous extract on the central system, respiratory system,urinary-sweat system, circulatory system and digestive system of the rat model of wind-cold exterior pattern, and clarify the scientific connotation of the medicinal properties of ephedra. Methods: The animal model of wind-cold exterior pattern was constructed by fan blowing plus cold stimulation. The rats showed sneezing, runny nose, crouching and elevated body temperature indicating successful modeling. After the success of the model, rats were divided into model group, positive drug acetaminophen group(0.455 g/kg), ephedra aqueous extract low dose group(1.170 g/kg), medium dose group(2.340 g/kg) and high dose group(4.680 g/kg). After continuous intragastric administration for 4 days, observe the general conditions of the rats and detect the central system indicators(such as body temperature, activity, sleep time, serum IL-4, IFN-γ levels), respiratory system indicators(such as Ammonia cough induction test, phenol red excretion), urinary-sweat system indicators(such as sweat gland slices, sweat secretion, urine output, and urine CRE and BUN levels), circulatory system indicators(such as heart function and serum NO levels), digestive system indicators(such as gastric residual rate, gastric emptying rate, small intestine propulsion rate and plasma MTL, GT and SST levels). The correlation analysis of the indicators of these five major systems was performed to comprehensively evaluate the ascending, and floating properties of ephedra. Results: The medium dose of ephedra aqueous extract(2.340 g/kg) was the best dose to improve the wind-cold e exterior pattern. The ‘ascending and floating’medicinal properties of ephedra were reflected in: it improved the temperature, activity distance and sleep time of rats with windcold exterior pattern to play a central excitatory role(P<0.05, P<0.01). It prolonged the cough latency period and reduced the times of coughs in rats with wind-cold symptoms topromote the lung qi(P<0.05, P<0.01);it increased the sweating and urine volume of rats in the model to release cold(P<0.05, P<0.01);it did not affect the circulatory system. The digestive boosting effects of high doses of ephedra aqueous extract(P<0.01) may be related to its side effects. Conclusion: The ‘ascending and floating’ medicinal properties of ephedra are reflected in the ‘promoting lung qi’ and ‘dispersing wind-cold’ in the model of wind-cold exterior pattern.