Coronary vasoconstrictor effect of ghrelin is not mediated by growth hormone secretagogue receptor 1a type in dogs

▶ GHS-R1a and GHS-R1b receptors are present in the wall of canine coronary arterioles. ▶ Ghrelin constricts isolated canine coronary arterioles in a tone-dependent manner. ▶ This vasoconstrictor effect is mediated by a receptor other than GHS-R1a.