Objectives: To investigate the effect of H. trifoliata on: (a) acetic acid-induced ulcers, (b) food intake, (c) water intake, (d) weight gain, (e) gastric acid secretion in rats.
Design: Comparative study.
Setting: Laboratory.
Subjects: 20 female Sprague Dawley rats (220 to 250 g) with acetic acid-induced peptic ulcers randomly assigned to test and control groups (n = 10). The test rats were allowed water and normal rat diet comprising 20% H. trifoliata ('Dombwe) and 'Imfe nkulu' in Shona and Ndebele respectively) for 17 days after ulceration while control rats were allowed water and normal rat diet for 17 days after ulceration. Thirty six other rats were prepared to study the effect of H. trifoliata on gastric and acid secretion stimulated by histamine, gastrin and carbachol.
Main outcome measures: Photographs of the gross anatomy and histology of test and control rat stomachs were taken. Daily food and water intake, weekly weight gain and gastric acid secretion were measured in the test and control rats.
Results: 17 days following the consumption of the H. trifoliata containing diet, macroscopically, no ulcers were found on the outer surface of the stomach walls of test rats. However, histological examination revealed traces of ulcer at the sites where ulcers were induced previously. In contrast, 70% of the control rats still had ulcers on the surface of their stomach walls. Histological examination showed massive denuded mucosa and submucosa at the ulcer sites which are signs of severe ulceration. Food intake in both groups was not significantly different except during the first three days when test rats consumed significantly less food (p < 0.01) than control rats. Daily water intake and weekly weight gain were also not significantly different in the test and control groups. H. trifoliata had no significant effect on gastric acid secretion stimulated by histamine, gastrin and carbachol.
Conclusions: H. trifoliata does not affect daily food and water intake and weekly weight gain in rats. It also does not affect histamine, gastrin and carbachol-stimulated acid secretion in rats. However, H. trifoliata accelerates the healing of acetic acid-induced peptic ulcer in rats. This may validate the use of H. trifoliata in the treatment of peptic ulcer in humans.