Adeyemi Olufunmilayo O, Ishola Ismail O, Okoro Uzodinma
Department of Pharmacology, Therapeutics and Toxicology, Faculty of Basic Medical Sciences, College of Medicine, University of Lagos, Lagos State, Nigeria.
Nig Q J Hosp Med. 2013 Oct-Dec;23(4):323-9.
Bryophyllum pinnatum Lam. Kurtz (Crassulaceae) is used in traditional African medicine in the treatment of diarrhoea.
To investigate the antidiarrhoeal action of the hydroethanolic leaf extract of Bryophyllum pinnatum (BP).
Normal intestinal transit, castor oil-induced intestinal transit, castor oil-induced diarrhoea, gastric emptying and enteropooling models in rodents were used to investigate antidiarrhoeal effect. The possible mechanism of antidiarrhoeal activity was investigated using prazosin (1 mg/kg, s.c; α1, adrenoceptor antagonist), yohimbine (1 mg/kg, s.c; α2 adrenoceptor antagonist), propranolol (1 mg/kg, i.p; α- adrenoceptor non-selective antagonist), atropine (1 mg/kg, s.c; muscarinic cholinergic antagonist), pilocarpine (1 mg/kg, s.c; muscarinic cholinergic agonist), and isosorbide dinitrate (IDN) (150 mg/kg, p.o; nitric oxide donor).
BP (25-100 mg/kg, p.o) produced dose-dependent and significant (P < 0.001) decrease in intestinal propulsion in normal and castor oil-induced intestinal transit models in comparison to distilled water (10 ml/kg, p.o.) treated control. This antidiarrhoeal effect was inhibited by propranolol pretreatment but yohimbine, prazosin, or atropine pretreatment failed to block this effect. BP treatment reduced the increased peristaltic activity induced by pilocarpine, however, co-treatment with IDN significantly (P < 0.001) enhanced the antidiarrhoeal effect of the extract. In castor oil-induced diarrhoea test, the extract produced a dose-dependent and significant (P < 0.001) increase in onset of diarrhoea, decreased diarrhoea score, the number and weight of wet stools when compared to control. The in vivo antidiarrhoeal index (ADI(in) vivo)) of 53.52 produced by the extract (50 mg/kg, p.o.) was similar to 76.28 ADI(in vivo) produced by morphine (10 mg/kg, s.c.). The extract produced dose- dependent and significant (P < 0.05; P < 0.001) decrease in the weight and volume of intestinal content in the intestinal fluid accumulation model. In gastric emptying test, BP treatment reduced the quantity of test meal emptied in 1 h but not significant.
The results showed that the hydroethanolic leaf extract of Bryophyllum pinnatum possesses antidiarrhoeal activity possibly mediated by interaction with β adrenoceptor, muscarinic cholinergic receptor and nitric oxide pathway.
落地生根（景天科）在非洲传统医学中用于治疗腹泻。
研究落地生根水乙醇叶提取物（BP）的抗腹泻作用。
采用正常肠道转运、蓖麻油诱导的肠道转运、蓖麻油诱导的腹泻、胃排空和肠积液模型研究抗腹泻效果。使用哌唑嗪（1mg/kg，皮下注射；α1肾上腺素能受体拮抗剂）、育亨宾（1mg/kg，皮下注射；α2肾上腺素能受体拮抗剂）、普萘洛尔（1mg/kg，腹腔注射；α肾上腺素能受体非选择性拮抗剂）、阿托品（1mg/kg，皮下注射；毒蕈碱胆碱能拮抗剂）、毛果芸香碱（1mg/kg，皮下注射；毒蕈碱胆碱能激动剂）和硝酸异山梨酯（IDN）（150mg/kg，口服；一氧化氮供体）研究抗腹泻活性的可能机制。
与蒸馏水（10ml/kg，口服）处理的对照组相比，BP（25 - 100mg/kg，口服）在正常和蓖麻油诱导的肠道转运模型中使肠道推进呈剂量依赖性且显著降低（P < 0.001）。普萘洛尔预处理可抑制这种抗腹泻作用，但育亨宾、哌唑嗪或阿托品预处理未能阻断此作用。BP处理可降低毛果芸香碱诱导的增强蠕动活性，然而，与IDN联合处理可显著增强提取物的抗腹泻作用（P < 0.001）。在蓖麻油诱导的腹泻试验中，与对照组相比，提取物使腹泻发作呈剂量依赖性且显著延迟（P <0.001），腹泻评分、湿粪数量和重量降低。提取物（50mg/kg，口服）产生的体内抗腹泻指数（ADI（体内））为53.52，与吗啡（10mg/kg，皮下注射）产生的76.28 ADI（体内）相似。在肠积液模型中，提取物使肠内容物重量和体积呈剂量依赖性且显著降低（P < 0.05；P < 0.001）。在胃排空试验中，BP处理可降低1小时内排空的试验餐量，但不显著。
结果表明，落地生根水乙醇叶提取物具有抗腹泻活性，可能通过与β肾上腺素能受体、毒蕈碱胆碱能受体和一氧化氮途径相互作用介导。
