Gastric acid anti-secretory effects of aqueous leaf extract of Nauclea latifolia (Rubiaceae) in rats

Abstract

The aqueous leaf extract of Nauclea latifolia has been shown to have anti-ulcer effect. Objectives: The present study was undertaken to investigate the effects of aqueous leaf extract of N. latifolia on gastric acid secretion as the possible mechanism of its anti-ulcer actions in male albino rats. Materials and Methods: A total of sixty (60) male albino rats were divided into two experimental studies of thirty (30) rats each. Each of the experimental studies was further divided into groups according to study design. The extract was administered orally at the doses of 100, 200 and 400 mg/kg for the experimental groups while the control and reference groups received distilled water (2 ml/kg, p.o) and cimetidine (32 mg/kg, p.o) respectively, 60 minutes prior to oral administration of indomethacin (30 mg/kg) to induce gastric mucosal injury. In the second study, gastric acid output was measured by the continuous perfusion of rat’s stomach under anesthesia with normal saline at the rate of 1 ml/min. Results: Phytochemical analysis revealed the presence of saponins, tannins, flavonoids, alkaloids and cardiac glycosides. Acute toxicity studies showed there were no deaths within 24 h after the application of the extract up to 1600 mg/kg B.W (i.p). Rats pre-treated with N. latifolia exhibited significant (P<0.05), and dose-dependent inhibition of indomethacin-induced gastric ulceration. A significant decrease in gastric acid secretion was produced by the extract at all doses studied. Conclusion: Findings of this study suggest that, aqueous extract of N. latifolia significantly reduced gastric acid secretion in indomethacin-induced gastric ulceration by inhibiting histamine-stimulated gastric acid secretion probably by occupying H2 - receptors in rats.