The Mechanisms of Action of Interleukin-1 on Rabbit Intestinal Epithelial Cells

Abstract

Interleukin-1 (IL-1) is an inflammatory mediator that increases Cl- secretion in intestinal epithelial cells. To identify the signal transduction pathway(s) involved in IL-1's action, cells were treated with IL-1 and the levels of cyclooxygenase (COX) enzymes, prostaglandin E2 (PGE2) and phospholipase A2-activating protein (PLAP), and the activity of phospholipase A2 (PLA2) were measured. IL-1 caused concentrationand time-dependent increases in the levels of PLA2 activity, and/or in the levels of PLAP, COX-2 and PGE2. The IL-induced increase in PGE2 levels was biphasic, with the first peak due to the increase in PLAP levels, and the second peak due to the increase in COX-2 levels. This increase in PGE2 levels may provide a mechanism for acute and chronic inflammation in the intestine.

Keywords

• Interleukin-1 receptor
• Cytokines
• Prostaglandin E2 production
• Epithelial cells
• Inflammatory bowel disease.