Involvement of prostaglandins in inflammation induced by latex ofCalotropis procera

[摘要] INTRODUCTION: The aerial parts of the plantCalotropis proceraproduce milky white latex that causes inflammation of the skin and mucous membranes. Prostaglandins are one of the mediators released in an inflammatory response following induction of cyclooxygenase (COX). In the present study, we have evaluated the role of prostaglandins in inflammatory response elicited by the latex ofC. procera.Methods: Aqueous extract of dried latex ofC. procerawas injected into the 6-day air-pouch in the rat. The inflammatory response was evaluated by studying the air-pouch fluid for its volume, protein and prostaglandin (PG) E2concentrations, and leucocyte counts. The granulation tissue from the pouch was quantified and studied for COX-2 expression by reverse transcriptase-polymerase chain reaction. The inhibitory effect of celecoxib and dexamethasone was evaluated on the aforementioned parameters.Results: Dried latex produced an inflammatory response that was maximum at 6 h. It was associated with the accumulation of protein-rich fluid, leucocytes and PGE2production. It also resulted in granulation of the pouch cavity that was a maximum on day 3. COX-2 expression could be detected in the granulation tissue on day 1 and it increased progressively up to day 5. The anti-inflammatory drugs celecoxib and dexamethasone significantly attenuated the inflammatory response and inhibited COX-2 expression in granulation tissue.Conclusions: Latex ofC. procerainduces an inflammatory response characterized by an early exudative phase accompanied by PGE2production and a late proliferative phase associated with COX-2 induction. Both the phases were effectively inhibited by COX-2 inhibitors.

[学科分类] 生理学与病理学