枇杷叶不同提取物的止咳化痰平喘作用比较研究

Comparative study of different extracts of loquat leaf in antitussive and expectorant and antiasthmatic effects

目的:通过对生枇杷叶和炙枇杷叶的水提物、醇提物止咳化痰平喘作用进行比较,为枇杷叶临床应用和制剂工艺提供科学依据。方法:分别制备枇杷叶生品和炙品的水提物和醇提物,以小鼠氨水引咳法和豚鼠枸橼酸引咳法观察枇杷叶不同提取物的镇咳作用,小鼠气管酚红排泌试验观察祛痰作用,组胺和乙酰胆碱豚鼠引喘模型观察平喘作用。结果:炙品水提能显著延长小鼠(10g/kg)和豚鼠(5g/kg)咳嗽潜伏期、减少小鼠咳嗽次数、增加小鼠呼吸道排泌量、延长豚鼠喘息潜伏期,明显减少豚鼠咳嗽次数,与同剂量的生品水提、炙品醇提比较均有明显差异。结论:蜜炙枇杷叶的止咳化痰平喘总体效果明显优于生枇杷叶,而且水提物优于醇提物。

Through the study on different extract of Loquat leaf in antitussive and expectorant and control asthma effects, provide sci- ence references for clinical application and preparation process. Methods： Preparaing water extract and alcohol extract of the crude Loquat leaf and those concocted by honey, cough model induced by ammonia liquor in mice and citric acid in guinea pigs were used to observe the antitussive effects, the method of phenol red execretion in mice was used to investigate expectorant effects and bronchial asthma model in- duced by histamine acetylcholine in guinea pigs used to observe the antiasthmatic effects. Results： Aqueous extract of honey concocted Loquat leaf significantly prolonged the incubation period of cough in mice（lOg/kg） and guinea pigs（5g/kg）, decreased cough frequency and respir- atory excretion in mice, inhibited the asthma in guinea pigs （ P 〈0. 01 ） , obviously decreased cough frequency in guinea pigs （ P 〈 0. 05）, those effects showed significant differences when it compared with aqueous extract of crude Loquat leaf and alcohol extract of honey concocted Loquat leaf in same dosage. Conclution： The overall effects of honey concocted Loquat leaf are superior than the crude, and the alcohol ex- tract better than the water extract, those results scientifically verified the traditional Chinese medicine theory of ＂loquat leaf should be concoc- ted with honey for antitussive use＂.