Roles of cyclooxygenase-2 and prostaglandin E receptors in gastric mucosal defense in Helicobacter pylori-infected mice.

Abstract

BACKGROUND/AIM:

Helicobacter pylori (H. pylori) induces cyclooxygenase-2 (COX-2) expression. The aim of this study was to assess the roles of COX-2 and PGE2 receptors (EPs) in gastric defense in H. pylori-infected mice.

METHODS:

Gastric lesions were induced by oral administration of 0.15N HCl in 60% ethanol (HCl/EtOH) to mice infected with H. pylori, and macroscopically evaluated 30 min later. Mice were administered NS-398 (COX-2 selective inhibitor) concomitantly with selective EP agonists 4 hours before HCl/EtOH challenge.

RESULTS:

H. pylori infection prevented the gastric damage induced by HCl/ EtOH, and this protective effect was abolished by NS-398. Selective agonists of EP1, EP2, and EP4, but not the EP3 agonist, reversed the inhibitory effect of NS-398 on prevention of damage by H. pylori infection. The EP4 agonist and EP2/EP4 agonists inhibited the increase in TNF-alpha mRNA expression and neutrophilic infiltration caused by NS-398, respectively.

CONCLUSION:

COX-2-derived PGE2 may play an important role in resistance to HCl/EtOH damage in H. pylori-infected mice by activating EP1, EP2, and EP4.

• Authors: K Taira, T Watanabe, T Tanigawa, M Shiba, K Tominaga, Y Fujiwara, N Oshitani, K Higuchi, T Arakawa
• Journal: Inflammopharmacology (Inflammopharmacology) Vol. 15 Issue 3 Pg. 132-8 (Jun 2007) ISSN: 0925-4692 [Print] Switzerland
• PMID: 19847955 (Publication Type: Journal Article)

Chemical References

• Nitrobenzenes
• Ptger1 protein, mouse
• Ptger2 protein, mouse
• Ptger4 protein, mouse
• Receptors, Prostaglandin E
• Receptors, Prostaglandin E, EP1 Subtype
• Receptors, Prostaglandin E, EP2 Subtype
• Receptors, Prostaglandin E, EP4 Subtype
• Sulfonamides
• Tumor Necrosis Factor-alpha
• N-(2-cyclohexyloxy-4-nitrophenyl)methanesulfonamide
• Ethanol
• Ptgs2 protein, mouse
• Cyclooxygenase 1
• Cyclooxygenase 2

Topics

• Animals
• Cyclooxygenase 1 (analysis)
• Cyclooxygenase 2 (analysis, physiology)
• Ethanol (toxicity)
• Female
• Gastric Mucosa (immunology, microbiology)
• Helicobacter Infections (immunology)
• Helicobacter pylori
• Mice
• Mice, Inbred C57BL
• Nitrobenzenes (pharmacology)
• Receptors, Prostaglandin E (physiology)
• Receptors, Prostaglandin E, EP1 Subtype
• Receptors, Prostaglandin E, EP2 Subtype
• Receptors, Prostaglandin E, EP4 Subtype
• Sulfonamides (pharmacology)
• Tumor Necrosis Factor-alpha (physiology)