5-HT(1Dβ) receptor mediates the supersensitivity of isolated coronary artery to serotonin in variant angina

Abstract

Although serotonin (5-hydroxytryptamine; 5-HT) is used for provocation of coronary spasm, 5-HT receptor subtypes in spastic coronary arteries remain undetermined. We demonstrated the supersensitivity of isolated coronary artery to ergonovine, 5-HT, and sumatriptan, a 5-HT(1D) receptor agonist, in a patient with variant angina. Furthermore, we detected gene expression of 5- HT(1Dβ) and 5-HT(2A) receptors in spastic coronary artery using RNase protection assay. These findings suggest that the leftward shift of the dose- response curve for 5-HT, which plays an important role in the pathogenesis of coronary spasm, is mediated by activation of 5-HT(1Dβ) receptor.