Adeyemi O O, Aigbe F R, Badru O A
Department of Pharmacology, Faculty of Basic Medical Sciences, College of Medicine, University of Lagos, P.M.B. 12003, Nigeria.
Nig Q J Hosp Med. 2012 Jan-Mar;22(1):29-33.
Aristolochia ringens, an ornamental plant native to tropical America that now grows in a number of African countries has been reported to be used in African traditional medicine for the management of snake bite venom, gastrointestinal disturbances, rheumatoicd arthritis and insomnia among others.
Based on its use in traditional African medicine, the antidiarrhoeal activity of the aqueous root extract of Aristolochia ringens (AR) was evaluated to determine the pharmacological basis of its use in the management of diarrhoea.
Normal and castor oil (CO) induced intestinal transit, castor oil induced diarrhoea, gastric emptying and enteropooling models were carried out in mice and rats. Preliminary phytochemical screening and acute toxicity tests were also carried out.
AR (100-400 mg/kg, p.o.) produced a dose-dependent and significant decrease in normal and castor oil-induced intestinal transit compared to the vehicle group. This effect was significantly (p < 0.001) inhibited by pilocarpine (10 mg/kg, s.c.), phentolamine and propranolol (1 mg/kg, i.p.) respectively but neither significantly inhibited by yohimbine (1 mg/kg, s.c.) nor significantly enhanced by isosorbide dinitrate (150 mg/kg, p.o.). AR produced a dose-dependent and significant increase in the latency of diarrhoeal onset. AR also reduced the diarrhoeal score, number and weight of wet stools. The in vivo antidarrhoeal index (ADI(in vivo)) of 81.79 produced by AR (400 mg/kg) is comparable to the 86.85 ADI(in vivo). produced by morphine (10 mg/kg, s.c.). AR also reduced the gastric enteropooling and emptying effects of castor oil. Preliminary screening showed the presence of tannins, saponins and alkaloids. In the acute toxicity study, no mortality was observed with AR administered orally up to 10,000 mg/kg, but an LD50 of 407.38 mg/kg was obtained with the intraperitoneal route of administration in mice.
Results show that the aqueous root extract of Aristolochia ringens possesses antidiarrhoeal activity possibly mediated by its non selective action on adrenoceptors in the GIT and physiological antagonism of the parasympathetic nervous system.
马兜铃（Aristolochia ringens）是一种原产于热带美洲的观赏植物，现生长于多个非洲国家，据报道在非洲传统医学中被用于治疗蛇咬毒液、胃肠道紊乱、类风湿性关节炎和失眠等病症。
基于其在非洲传统医学中的应用，对马兜铃水根提取物（AR）的止泻活性进行评估，以确定其用于治疗腹泻的药理学依据。
在小鼠和大鼠中进行正常及蓖麻油（CO）诱导的肠道转运、蓖麻油诱导的腹泻、胃排空和肠内积液模型实验。还进行了初步的植物化学筛选和急性毒性试验。
与赋形剂组相比，AR（100 - 400 mg/kg，口服）使正常及蓖麻油诱导的肠道转运呈剂量依赖性显著降低。毛果芸香碱（10 mg/kg，皮下注射）、酚妥拉明和普萘洛尔（1 mg/kg，腹腔注射）分别显著（p < 0.001）抑制了这种作用，但育亨宾（1 mg/kg，皮下注射）未显著抑制，硝酸异山梨酯（150 mg/kg，口服）也未显著增强这种作用。AR使腹泻发作潜伏期呈剂量依赖性显著延长。AR还降低了腹泻评分、湿粪的数量和重量。AR（400 mg/kg）产生的体内止泻指数（ADI（体内））为81.79，与吗啡（10 mg/kg，皮下注射）产生的86.85 ADI（体内）相当。AR还降低了蓖麻油的胃内积液和排空作用。初步筛选显示存在单宁、皂苷和生物碱。在急性毒性研究中，口服给予AR高达10,000 mg/kg未观察到死亡，但在小鼠腹腔注射给药时获得的半数致死量（LD50）为407.38 mg/kg。
结果表明，马兜铃水根提取物具有止泻活性，可能是通过其对胃肠道肾上腺素能受体的非选择性作用以及副交感神经系统的生理拮抗作用介导的。
