Analysis of the responses of the fetal vessels of human perfused placental lobules to acute infusions of arachidonic acid

Abstract

The vasodilatory response to arachidonic acid by the fetal vessels of human perfused placental lobules, in which tone had been increased by infusion of the thromboxane A2 mimetic U46619, was significantly reduced in the presence of the prostacyclin (PGI2) synthetase inhibitor tranylcypromine compared with saline infusion controls. HPLC analysis of the fetal effluent from human perfused placental lobules, in which radiolabelled arachidonic acid had been infused, identified two peaks of activity. The first peak displayed an elution profile similar to that of a 6-keto-PGFlα standard; the presence of 6-keto-PGF1α in this peak was confirmed by RIA. The second peak had an elution profile similar t..