Prostacyclin (PGI2) release accompanying angiotensin conversion in rat mesenteric vasculature

Abstract

The relationship between angiotensin conversion and release of prostaglandins (PGs) was studies in isolated, perfused, mesenteric vasculature of rats. PGs in the mesenteric effluent were detected by bovine coronary artery and rat stomach strip, and by radioimmunoassay of 6-oxo-PGF1α and PGE2. Angiotensin II (AII) was assayed simultaneously using rabbit aorta. Both angiotensin I (AI) and AII released a prostacyclin (PGI2)-like substance, but little PGE2 from the mesentery, AII being 5 times more potent. Indomethacin (2.8 μM) abolished angiotensin-induced release of PGI2. Of the AI (0.2-1.5 nmol) injected into the perfusion medium, 3-8% was converted to AII in passage through the mesentery. Ca..