Ulceroprotective Effect of Methanol Extract of Psidium guajava Leaves on Ethanol Induced Gastric Ulcer in Adult Wistar Rats

The present study investigates the anti-ulcer activity of methanol extract of P. guajava on ethanol induced gastric ulceration in adult Wistar rats. Twenty nine adult non pregnant female Wistar rats weighing between 160-225 g were used for the study. Five rats were used for the acute oral toxicity test in accordance with the OECD guidelines 425. The remaining 24 rats were randomly divided in 4 groups of 6 rats each. Groups I and II which served as negative and positive controls orally received 2 mL/Kg body weight of distilled water and 50 mg/kg ranitidine respectively for a period of 10 days while groups III and IV were administered 500 and 1000 mg/kg of methanol extract of P. guajava leaves respectively also for 10 days. The next day, ulcer was induced by oral administration of 1 mL of 90% ethanol in all the groups after overnight fasting. The animals were sacrificed 1 h after induction of gastric ulceration and the stomachs were removed, processed and examined using a 6X hand held magnifying lens and mean ulcerative indices were scored accordingly. The result for the acute oral toxicity test showed no mortality nor was there any physical sign of toxicity. Significant dose dependent decrease in ulcer indices was observed among the P. guajava leaves extract treated groups as compared to the control groups. The study concludes that methanol extract of P. guajava is non toxic in acute doses and confers ulceroprotective activity on ethanol induced gastric ulcer in adult Wistar rats.