Adaptation of Rat Gastric Mucosa exposed to Indomethacin: A Histological Study

Abstract

Background: Indomethacin is still used in the remote areas because of its low cost. It relieves pain, reduces swelling and tenderness. It induces gastric ulceration both in experimental animals and humans. This study was conducted to observe the reversible changes in the damaged gastric mucosa during its prolonged administration.

Material & Methods: In this study intrapertioneal injections of indomethacin were given to rats in maximum therapeutic dose (4mg/kg body weight) to three experimental groups B, C and D for one, two and three weeks respectively. Group A was the control group. Effects were observed in the stomach pylorus.

Results: There were well-defined superficial ulcers during initial two weeks of drug administration. During third week, there was minor damage in the form of focal necrosis. Morphometric analysis initially showed increase in the number of goblet cells, columnar cells, and mitotic figures, which was part of the tissue response to an injury. These findings were significantly reduced with continued use of the drug. The unusual phenomenon observed was that when the duration of the drug was prolonged, the ulcerogenic effects of the drug were reduced.

Conclusion: Indomethacin given in a maximum therapeutic dose initially induces lesions in stomach but almost no effects are noted when the duration of drug administration is prolonged. This unusual response is due to adaptation of gastric mucosa to the continued use of the drug.