Apelin-13
Overview
Apelin-13 is a 13-amino acid endogenous peptide that represents the most potent and abundant isoform of the apelin family. It acts as the ligand for the APJ receptor (also known as the apelin receptor), a G protein-coupled receptor expressed in vascular endothelium, cardiomyocytes, and other tissues. The peptide induces vasodilation, enhances cardiac contractility, and modulates fluid homeostasis, providing therapeutic rationale for heart failure and pulmonary hypertension. Its structure consists of a highly conserved C-terminal sequence critical for receptor binding and biological activity.
Key Research Findings
Preclinical studies in rodent models have demonstrated improved cardiac output, reduced afterload, and attenuated pathological remodeling following apelin-13 administration. Clinical translation has been limited, with small exploratory human studies suggesting hemodynamic benefits in heart failure patients, but no large-scale randomized controlled trials have been completed to date. Further investigation is needed to establish safety and efficacy profiles for clinical use.
Intravenous
Research Phase
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