瑶药红花夹竹桃生药学及药理毒理作用研究

Study on Quality Control and Pharmacological and ToxicologicalEffects of Nerium Indicum Mill

目的:对瑶药红花夹竹桃进行生药学及药理毒理作用研究。方法:采用基源鉴别、药材性状鉴别、显微鉴别、薄层色谱法对红花夹竹桃特征进行鉴别研究。参照《中华人民共和国药典》2015版四部通则中的方法对10批次样品进行水分、总灰分、酸不溶性灰分及浸出物等项目进行检查。采用浓氨水喷雾引咳法,观察红花夹竹桃水提物的止咳效果。采用概率单位法(Bliss法)测定LD50,评价其急性毒性作用。结果:详细描述红花夹竹桃原植物形态,明确其根、茎、叶的组织结构特征及粉末鉴别特征,初步建立红花夹竹桃薄层色谱鉴别方法。建议该药材质量水分不超过13.0%,总灰分不超过8.0%,酸不溶性灰分不超过2.0%,浸出物不少于7.5%。药材水提物高剂量(0.6 g/kg)能明显减少浓氨水导致小鼠咳嗽潜伏期和咳嗽次数。Bliss法小鼠灌胃给药半数致死量LD50=13.311 g/kg,LD5095%的可信限=11.882-14.913 g/kg。结论:瑶药红花夹竹桃药材性状、显微特征明显,薄层色谱分离效果好,重现性佳。该药材具有明显的止咳作用,但毒性较大。研究结果将为瑶药材红花夹竹桃质量控制及进一步开发利用提供参考。

Objective:To establish a quality standard control method for the crude drug derived from Nerium indicum Mill.in Guangxi and explore and appraise the pharmacological and toxicological effects of that crude drug,so as to provide a foundation for its quality standard preparation,clinical efficacy,and safe application.Methods:The morphology of the species was investigated.The microscopic characteristics of roots,stems,leaves and powder were identified under microscope.TLC was used for qualitative identification.Referring to the general chapters of Chinese Pharmacopoeia(2015 edition),the water content,total ash,acid insoluble ash and extract were studied.Mouse models with cough induced by concentrated ammonia solution water spray were used to observe the antitussive effect of different concentrations of water extracts.The Bliss method was used to determine LD 50 to evaluate the acute toxicity in mice.Results:The morphological characteristics as well as microscopic characteristics of roots,stems,leaves and powder were determined,and a TLC method was established.Results of pharmacological studies show that,as compared with the blank control group,the high water extract dose group(0.6g/kg)had significantly reduced cough latency and cough frequency of mice with cough induced by concentrated ammonia solution(P<0.05),suggesting that the drug was effective in relieving cough.The acute toxicity test results show that LD 50 was 13.311g/kg with the 95%confidence limits being 11.882-14.913 g/kg.Conclusion:The crude drug have distinct morphological and microscopic characteristics.The TLC exhibits good and reproducible separation.Based on the water contents,total ash,acid-insoluble ash,and extracts of 10 batches of crude drug collected in Guangxi,it is suggested that the water content,total ash,and acid-insoluble ash should not be higher than 13.0,8.0%,and 2.0%,respectively,and the content of extracts should not be lower than 7.5%for crude drug quality standard.The drug has a good cough-relieving effect but it is highly toxic.Our results may be used as a reference for further development and utilization as well as preparation of quality standards of the drug.