The Role of Mucosal Prostaglandin Levels in Healing of Water Immersion-Induced Gastric Ulcers in Rats

Abstract

This study was designed to clarify the recovery time course of water immersion stress ulcers. Rats were divided into two groups: the control group and the cetraxate group. In the cetraxate group, 6 h after water immersion stress, Cetraxate (300 mg/kg) was administered intragastrically twice a day until the end of the experiment. Ulcer indices were observed immediately, 1, 3, 7, 14, and 21 days after water immersion stress in each group. Changes in gastric mucosal prostaglandin (PG) levels were measured by means of high-performance liquid chromatography. In the control group ulcer healing was not observed within 1 day after stress. Gastric lesions had decreased significantly after 3 days, but 21 days were required for total healing. Accelerated ulcer healing was observed in the cetraxate group. Four kinds of PGs were detected in gastric mucosa: 6-keto-PGF_1α, PGF_2α, PGE₂, and PGD₂. Recovery of PG levels differed from each other. Fourteen days were required for full recovery of PGD₂ and 6-keto-PGF_1α. In contrast, 7 days were required for recovery of PGF_2α and PGE₂. Cetraxate accelerated the recovery of gastric mucosal PGD₂ and 6-keto-PGF_1α levels, especially the former. These results suggest that PGs, especially PGD₂, are linked with the healing processes of stress ulcers.

Key Words:

• Cetraxate
• prostaglandins
• recovery course
• stress ulcer