目的：研究桑白皮水煎液及化学拆分组分的止咳祛痰平喘作用。方法：采用氨水诱咳法观察止咳作用；小鼠酚红排泌法观察祛痰作用；组胺与乙酰胆碱引喘法观察平喘作用；离体气管法观察解痉挛作用。结果：与空白组比较，桑白皮水煎液低、中、高剂量组均能显著减少小鼠咳嗽次数、增加小鼠呼吸道的酚红排泌量、延长豚鼠哮喘潜伏期、提高解痉率，以中剂量效果最好。各化学拆分组分与空白组相比，桑白皮30%、50%乙醇组分能明显减少浓氨水引起小鼠咳嗽的次数并延长咳嗽潜伏期、增加小鼠呼吸道的酚红排泌量（P<0.05或P<0.01），30%乙醇组分、脂肪油组分能延长豚鼠哮喘潜伏期（P<0.05或P<0.01），此外，30%乙醇组分能使气管收缩幅度明显降低，具有一定的解痉挛作用。结论：桑白皮水煎液具有较好的止咳、祛痰、平喘作用，其有效部位为30%乙醇组分，用量相当于中剂量的1/3，其止咳、祛痰、平喘作用最为显著，与水煎液中剂量作用相当。

This study was aimed to investigate the antitussive, expectorant and antiasthmatic effects of aqueous extracts and the chemical split fractions of Mori Cortex. Cough mice models induced by ammonia water were used to observe the effect on arresting cough. The phenol red expectoration method in mice was used to observe the effect on expelling phlegm. Histamine and acetylcholine mixture induced asthma model was used to observe the effect on relieving asthma. Isolated trachea model was used to observe the effect on relieving spasm. Compared with the control group, the low, medium and high doses of aqueous extracts of M. Cortex can obviously decrease the frequency of cough, increase phenol red output of trachea in mice, prolong the latent period of asthma in guinea pigs, and increase the antispasmodic rate. The medium dose had the best effect. The comparison between different chemical split fractions of M. Cortex and the control group showed that the 30% and 50% ethanol fraction of M. Cortex can obviously decrease the frequency of cough and prolong the latent period of cough induced by ammonia water in mice, increase phenol red output of trachea in mice (P<0.05 or P<0.01); and 30% ethanol fraction and fatty oil fraction can prolong the latent period of asthma in guinea pigs (P< 0.05 or P<0.01). In addition, 30% ethanol fraction can obviously reduce the degree of tracheal contraction. It had certain effect of relieving spasm. It was concluded that aqueous extracts of M. Cortex had better effects on relieving cough, expectorant and antiasthma. The effective part was the 30% ethanol fraction, which was the dose equivalent of 1/3 of the medium dose. It had significant effect on relieving cough, expectorant and antiasthma. The effect was equivalent to the medium dose of aqueous extracts of M. Cortex.

科学技术部国家重点基础研究发展计划“973计划”（2013CB531802）：宣泻利水中药的药性研究，负责人：郑晓珂。