Experiment study on the safety of selective COX-2 inhibitor-celecoxib on gastric mucosa

Objective To compare the gastric mucosa damage induced by celecoxib and conventional NSAIDs——indomethacin. Methods NSAIDs induced gastric mucosal damage model in rats was obtained by pouring indomethacin, celecoxib respectively (n=8); After gastric damage induced by means of 100% ethanol, celecoxib were administered by gastric gavage (n=8). Gastric mucosal 6-keto-PGF 1α ,TXB 2 level and lesion index (LI) were measured. Morphological changes of gastric mucosa were assessed under light and scanning electronic microscopy. Results Indomethacin caused obvious gastric damage (LI:13.38±2.06) and a marked reduction of 6-keto-PGF 1α ,TXB 2 level was observed (P0.01). Celecoxib did not produce necrotic injuries in healthy gastric mucosa (LI:0), but the injuries previously induced by ethanol worsened (LI:37.19±3.34 vs 19.90±2.28,P0.01). Conclusions Inhibition of COX-1 is the major mechanism of NSAIDs associated gastric mucosa damage. As a selective COX-2 inhibitor, celecoxib did not produce toxic injuries on healthy gastric mucosa, thus it is safer on gastric mucosa than conventional NSAIDs. However, when administered in presence of altered gastric mucosa, it worsened gastric injuries.