Abstract:
Problem statement: Gastrointestinal ulcers account significantly for morbidity and
mortality in Ghana. The study therefore investigated the gastroprotective effect of an ethanolic root
bark extract of Zanthoxylum zanthxyloides and its safety for us. Approach: Gastric ulceration was
induced in Sprague-Dawley rats with Indomethacin (25 mg kg−1, p.o) and was treated with 150, 250, or
500 mg kg−1 of the extract, or 20 mg kg−1 Esomeprazole. The number of ulcers per stomach, Ulcerative
Index and Curative Ratio were determined. A histological study of the gastric mucosa was also
performed. The extract’s effect on an isolated guinea-pig ileum preparation was investigated to
elucidate its possible mechanism of action. Safety assessments involving, organ weight to body weight
ratio determination, hematological analysis and liver function tests were performed. Results: The
extract significantly decreased (p≤0.001) the number of ulcers per stomach and the Ulcerative Index
(similar to Esomeprazole) and significantly increased (p≤0.001) the Curative Ratio in a dose-dependent
manner. It completely corrected the architectural distortions caused by gastric ulceration and inhibited
significantly (p≤0.001) the contractile responses of the isolated guinea-pig ileum to Acetylcholine,
Nicotine and Histamine in a manner comparable to reference antagonists. The extract had no
significant effect (p>0.05) on organ weight to body ratio and hematological profile. Plasma levels of
Alanine transaminase and Alkaline phosphatase decreased significantly (p≤0.001) in extract and
Esomeprazole-treated ulcerated rats. Levels of Gamma-glutamyl transferase, Total bilirubin (direct
and indirect) however increased significantly (p≤0.01-0.001). Conclusion/Recommendations: Per the
findings, the ethanolic root bark extract of Zanthoxylum zanthoxyloides has gastroprotective effect in
Sprague-Dawley rats working possibly via antimuscarinic or antihistaminic mechanism. It however has
a potential of causing cholestasis hence liver function should be monitored.
