Amplification of Responses to Sumatriptan by Various Agonists in Rabbit Isolated Iliac Artery

Abstract

Rabbit iliac arteries (IA) were almost unresponsive to the serotonin (5-HT1-like) receptor agonist sumatriptan under control conditions, whereas this agent elicited concentration-dependent contractions in IA rings given a moderate tone by threshold concentrations (EC10-EC20) of prostaglandin F2α, (PGF2α), angiotensin II (AII), histamine. norepinephrine (NE), phenylephrine (PE), or potassium chloride. These results suggest that 5-HT1like receptors are uncovered not only by histamine or thromboxane/prostaglandin receptor agonists, as shown in rabbit renal and femoral arteries, but also by various agonists in rabbit IA as shown in this study.