[Selective COX-2 inhibitor delays experimental gastric ulcer healing by stimulating gastric acid secretion in rats].
OBJECTIVE
To observe the effect of selective cyclooxygenase-2 (COX-2) inhibitor on the healing of experimental gastric ulcer in rats and explore its mechanisms in light of gastric acid secretion.


METHODS
Gastric ulcers were induced in rats by an application of acetic acid to the serosal surface of the anterior gastric body. The effects of selective COX-2 inhibitor, celecoxib, on the healing of gastric ulcer, the total acidity of gastric juice, the expressions of H+, K+-ATPase mRNA and protein, and the ultrastructure of the parietal cell were observed in comparison with the effects of normal saline.


RESULTS
Nine days after ulcer induction, the ulcer area was 11.9-/+3.1 mm square and 19.7-/+3.8 mm square in rats with normal saline and celecoxib treatments, respectively (P<0.01). The total acidity of gastric juice and the expressions of H+, K+-ATPase mRNA and protein in celecoxib group were significantly higher than that in normal saline group at both 6 and 9 days after ulcer induction, but no significant difference was found between the two groups in the amount of secretary canaliculus and microvillus.


CONCLUSIONS
Selective COX-2 inhibitor can significantly delay the healing of experimental gastric ulcer in rats, the mechanism of which might be associated with enhanced digestive action of gastric acid on the new granulation tissue at the ulcer base as a result of celecoxib-stimulated gastric acid secretion of the parietal cells.
Department of Gastroenterology, Nanfang Hospital, and Department of Nursing, Southern Medical University, Guangzhou 510515, China. hemr@263.net
Mei-rong
MR
He
Jin-qiu
JQ
Lin
Yu-gang
YG
Song
D000818:Animals; D000068579:Celecoxib; D052246:Cyclooxygenase 2 Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D005744:Gastric Acid / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D017506:H(+)-K(+)-Exchanging ATPase / Q000235:genetics / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008297:Male; D008871:Microvilli / Q000187:drug effects / Q000473:pathology; D010295:Parietal Cells, Gastric / Q000187:drug effects / Q000648:ultrastructure; D011720:Pyrazoles / Q000494:pharmacology* / Q000627:therapeutic use; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013276:Stomach Ulcer / Q000188:drug therapy* / Q000378:metabolism* / Q000473:pathology; D013449:Sulfonamides / Q000494:pharmacology* / Q000627:therapeutic use
D052246:Cyclooxygenase 2 Inhibitors; D011720:Pyrazoles; D012333:RNA, Messenger; D013449:Sulfonamides; D017506:H(+)-K(+)-Exchanging ATPase; D000068579:Celecoxib