Vasoactive Actions of Prostaglandins and Serotonin on Isolated Human Umbilical Arteries and Veins

Abstract

Cumulative responses to prostaglandins E 1 (PGE 1 ), E 2 (PGE 2 ), F 1α (PGF 1α ), and F 2α (PGF 2α ) were obtained on isolated human umbilical arteries and veins. All four prostaglandins produced contractions. PGF 2α was the most active prostaglandin on umbilical arteries, while PGE 2 and PGF 2α were equiactive and more potent than PGE 1 or PGF 1α on umbilical veins. 5-Hydroxytryptamine (5-HT) was at least 100 times more potent than the prostaglandins. SC-19220, a prostaglandin antagonist, in a high concentration was found to moderately antagonize the vasoactive effect of PGE 2 and to slightly antagonize contractions to 5-HT. Also, propylene glycol, the solvent for SC-19220, was observed to antagonize contractions to both PGE 2 and 5-HT, thereby indicating that solvent controls are necessary when evaluating compounds such as SC-19220.