Available online at www.sciencedirect.com Journal of Ethnopharmacology 116 (2008) 407–412 Antidiarrhoeal activity of the ethyl acetate extract of Baphia nitida (Papilionaceae) O.O. Adeyemi ∗ , A.J. Akindele Department of Pharmacology, College of Medicine, University of Lagos, P.M.B. 12003, Lagos, Nigeria Received 31 July 2007; received in revised form 13 November 2007; accepted 5 December 2007 Available online 14 December 2007 Abstract In our search for plants useful in the treatment of diarrhoea, we investigated the ethyl acetate extract of Baphia nitida (BN) using intestinal transit, enteropooling and gastric emptying tests in mice and rats. In the castor oil intestinal transit test, BN produced a significant (P < 0.05) dose dependent decrease in propulsion with peristaltic index (PI) values of 56.85 ± 6.76, 36.84 ± 3.04 and 31.98 ± 2.60%, respectively at doses of 100, 200 and 400 mg/kg vs. 89.33 ± 6.28% for control. The effect at 400 mg/kg was significantly lower than that of morphine, 10 mg/kg, s.c. (20.29 ± 3.78%), and was antagonized by isosorbide dinitrate, IDN (150 mg/kg, p.o.) but not by yohimbine (1 mg/kg, s.c.). This effect was not potentiated by atropine (1 mg/kg, s.c.). In the castor oil-induced diarrhoea test, BN produced a significant increase in onset of diarrhoea (103.40 ± 8.74, 138.80 ± 17.04 and 174.8 ± 29.04 min, 100 to 400 mg/kg, vs. 47.60 ± 8.76 min for control and 226.10 ± 12.57 min for morphine). The severity of diarrhoea (diarrhoea score) was dose dependently reduced (19.00 ± 2.26, 17.04 ± 1.89, 15.00 ± 2.05, 100 to 400 mg/kg, vs. 31.40 ± 2.11 for control and 7.7 ± 2.2 for morphine). This effect was not antagonized by IDN or yohimbine. The effect on severity was, however, potentiated by atropine. BN also reduced the number and weight of wet stools but did not have any significant effect on intestinal fluid accumulation and gastric emptying. Results obtained suggest that the ethyl acetate extract of Baphia nitida is endowed with antidiarrhoeal activity possibly mediated by interference with the l-arginine nitric oxide pathway and synergistic with antagonistic action on muscarinic receptors. © 2008 Elsevier Ireland Ltd. All rights reserved. Keywords: Baphia nitida; Diarrhoea; Antidiarrhoeal activity; Intestinal transit; Enteropooling; Gastric emptying 1. Introduction Baphia nitida Lodd (Papilionaceae) is a widely distributed plant most commonly found in the interior and coastal regions of tropical Africa. Commonly known as camwood, it appears mainly as shrubs or small trees with variable leaves pointed at the tip. The plant has a rich history of use as dyewood and shade provider, in addition to its use across West Africa in the treat- ment of various ailments (Daziel, 1937; Irwine, 1961). Known by diverse local names—Mbundoi (Sierra Leone), Okoue (Ivory Coast), Odwen (Ghana), Enum banjo (Cameroun), Igi osun, Abosi, and Majigi (Southwest, Southeast and Northern Nige- ria, respectively), the water and alcoholic extract of the stem, leaves and roots, as well as emulsion and ointments prepared from these parts, are employed in the treatment of skin, gastroin- testinal, inflammatory and venereal diseases. The haemostatic ∗ Corresponding author. Fax: +234 1 4936441. E-mail address: ooadey@yahoo.com (O.O. Adeyemi). (Kone-Bamba et al., 1987), neuromuscular (Adeyemi and Ogunmakinde, 1991), chronotropic and ionotropic (Adeyemi, 1992) and anti-inflammatory (Onwukaeme, 1995) effects of Baphia nitida have been investigated and reported. In respect of phytochemistry, constituents that have been identified in the plant include flavonoids, isoflavonoids, isoflavones, saponins, tannins, and alkaloids (Farnsworth and Euler, 1962; Odebiyi and Sofowora, 1978). Diarrhoea is one of the major health threats to populations in tropical and subtropical poor countries, responsible for about 5 million deaths annually, of which 2.5 million are children of less than 5 years (Heinrich et al., 2005). A study by Martinez et al. (1998), which looked at what form of treatment is admin- istered by primary care-takers of young children, demonstrated that herbal treatments are still important in the home treatment of diarrhoea. In essence, healers and patients in many communities still rely on locally available phytomedicines. As part of a broad based search for plants with antidiarrhoeal activity, this study was conducted to investigate the possible 0378-8741/$ – see front matter © 2008 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.jep.2007.12.004