Evaluation of the purgative properties of the ethanolic extract of Khaya senegalensis

Abstract

The purgative properties of the ethanolic extract of Khaya senegalensis was investigated on isolated rat jejunum and the whole animal. The dose–response effect of the extract and the reference drugs - acetylcholine (ACh) and histamine - on rat jejunum was investigated in vitro. The in vivo experiment consisted of verifying the increase in contractility of the rat jejunum, and also noting the degree of propulsion caused by charcoal meal which acted as a tracer in the rat intestine. The results showed that the percentage maximum change in amplitude and bath concentration for ACh, histamine and extract exhibited dose-dependent response. Maximum contraction was obtained for histamine, ACh and the extract at 1x10-2 mol/L, 1x10^-3 mol/L and 1x10^-2 mol/L respectively. The results for mean percentage transit time for charcoal showed that the extract produced a similar effect as the reference drug, sodium sulphate, which is an osmotic purgative. The degree of transition exhibited by the charcoal meal was dose-dependent with 600 mg/kg dose having the highest degree of transition. The experiment showed that the extract Khaya senegalensis increased gastrointestinal tract motility by acting via muscarinic and histamine receptors similar to effect produced by reference drugs ACh, histamine and sodium sulphate. The extract therefore could be said to exhibit purgative properties and might be of use in management of difficulties associated with defaecation or for constipation.

Key Words: Purgative; Constipation; Khaya senegalensis

Journal of Pharmacy and Bioresources Vol.1(1) 2004: 24-28