The role of leukotrienes in acute hypoxic pulmonary vasoconstriction in rats

Abstract

In this study, we investigated the possible role of leukotrienes in the mediation of hypoxic pulmonary vasoconstriction (HPV) in rats. Diethylcarbamazine citrate (DEC), an inhibitor of leukotriene synthesis, can block HPV, while minimally affecting the angiotensin II pressor response. The inhibition of HPV by DEC was not affected by cyclooxygenase or histamine H₁-receptor blocker, and the HPV response could be increased by cyclooxygenase blocker. It is suggested that the inhibitory effect of DEC on HPV may not be related to the actions of prostaglandins, histamine and angiotensin II. HPV in male Sprague-Dawley rats and female Hilltop rats was completely and significantly counteracted by the leukotriene receptor blocker FPL55712, respectively. This lends further support to the hypothesis that leukotrienes might be the most important mediators of HPV in rats.

Keywords

hypoxic pulmonary vasoconstriction / leukotrienes