Apelin-12 is a highly potent C-terminal fragment of a polypeptide that exhibits a strong affinity towards the orphan receptor APJ. It plays a role in maintaining body fluid balance and regulating feeding control in the central nervous system. Additionally, Apelin-12 functions as an inhibitor of HIV-1 entry through the APJ receptor and demonstrates neuroprotective properties.

Apelin-12 (A12) exhibits neuroprotection in ischemia-reperfusion injury by inhibiting JNK and p38 MAPK signaling pathways in mouse models [1]. It lowers arterial blood pressure in anesthetized rats through endothelial nitric oxide synthase activation and enhances myocardial function in rodent heart failure [2]. Additionally, A12 induces acid secretion by elevating histamine release in rat stomachs [4].