Elabela/Toddler-32  (ELA-32) has been identified as a new endogenous ligand for the apelin G protein coupled receptor (GPCR). Apelin levels have been shown to be reduced in heart failure and pulmonary arterial hypertension (PAH). ELA-32 delivery could be used to supplement the deficit of apelin. It can be cleaved to shorter forms Elabela/Toddler-21, and Elabela/Toddler-11. Apelin and ELA-32 share almost no sequence homology which is unusual for receptor ligands, it suggests a future for apelin receptor biased agonist design.

Exogenous administration of ELA-32 to rats has been shown to compensate for the downregulation of apelin seen in PAH. Further research into the potential of this peptide as an endogenous agonist reducing the severity of PAH could provide vital therapeutics in the future for cardiovascular disease.