Cyclooxygenase expression and mucosal PGE2 levels under the influx of low-dose aspirin and Helicobacter pylori

Aims: The mechanisms by which Helicobacter pylori (Hp) and low-dose aspirin induce gastric damage are not completely elucidated. Methods: Twenty healthy volunteers (Hp-positive, n=10, Hp-negative, n=10) received aspirin 100mg/die for 1 week. At day 0, 1, 3 and 7 esophagogastroduodenoscopy (EGD) was performed and biopsies from antrum and corpus mucosa were obtained. Hp-positive subjects underwent eradication therapy, and 3 months later 9 of them repeated the protocol. COX–1 and –2 were determined by immunohistochemistry (IHC) and RT-PCR; mucosal PGE2 levels were determined by ELISA. Results: COX–1, COX–2 transcri…