Apelin is an endogenous vasodilatory and inotropic peptide that is down-regulated in human pulmonary arterial hypertension, although the density of the apelin receptor is not significantly attenuated.
The apelin receptor is a potential target in the treatment of heart failure and pulmonary arterial hypertension where levels of endogenous apelin peptides are reduced but significant receptor levels remain.
Indeed, ongoing studies are investigating the potential benefits of apelin and apelin-mimetics for disorders such as heart failure and pulmonary arterial hypertension.