Inhibition of Gastric Mucosal Damage by Piper Nigrum (Black pepper) Pretreatment in Wistar Albino Rats

**Abstract.** The fruits of Piper nigrum Linn (Black pepper) are used as a spice in the intercontinental food preparation and have many therapeutic applications in the folk medicine. The present study on the ulcerogenic and/or anti-gastric ulcer activity of pepper was undertaken in view its large scale uses and a paucity of any systematic study. The investigation included (i) the effect of pepper (250 and 500 mg/kg) on normal gastric mucosa and (ii) The effect of Black pepper pretreatment on gastric mucosal injuries caused by different necrotizing agents (ethanol, NaCl, NaOH and indomethacin), pylorus ligation-accumulated gastric acid secretions, ethanol-induced changes in gastric mucus secretions, levels of non-protein sulfhydryl groups (NP-SH) and histopathological changes was investigated in rats. The results of preliminary experiments on the effect of Black pepper (alone) revealed lack of any effect. Pretreatment with Black pepper (250 and 500 mg/kg) was found to inhibit the ulcers induced by different necrotizing agents. It prevented the increase of gastric acid secretions, depletion of stomach wall mucus and prevented the histological changes caused by ethanol, however, there was no effect on the concentration of NP-SH in the gastric mucosa. The exact mechanism of protection is not clear, nevertheless, it might be related to the stimulation of bioenergetic processes in the gastric epithelium under the influence of piperine (the active constituent of Black pepper) on coenzyme Q10.