The 36-peptide apelin-36, which was originally detected in bovine stomach extracts, turned out to be the specific endogenous ligand of the orphan G protein-coupled receptor APJ. APJ has been shown to be a coreceptor for the infection of CD4-positive cells with HIV in the CNS, which can be blocked by apelin-36. APJ and the precursor peptide of apelin-36 are expressed in a variety of tissues including the heart, brain, breast, and lung; both are effective in the CNS and in the periphery.

Apelin-36 and its C-terminal fragments, especially (Pyr1)-Apelin-13, display a multitude of biological activities. Apelin-36 increases extracellular acidification rates and inhibits cAMP production in Chinese hamster ovary cells. The peptide acts as a hypotensive and positive inotropic agent. Apelin-36 and its fragments were reported to be involved in cell proliferation, vessel formation, cardiovascular functions (especially (Pyr1)-Apelin-13) and fluid homeostasis.

Recently, apelin was shown to be secreted by mature adipocytes, functioning as an adipokinin. Apelin-36 inhibited glucose-stimulated insulin production in vitro and in vivo.

Since plasma levels of apelin are altered in obese and hyperinsulinemic humans and in case of heart failure, apelin and fragments are valuable tools in obesity, diabetes and cardiovascular research.

Bachem offers the following Apelin products:


  • H-4896: Apelin-36 (human)
  • H-6302: Apelin-17 (human, bovine, mouse, rat)
  • H-4566: Apelin-13 (human, bovine, mouse, rat)
  • H-4568: (Pyr1)-Apelin-13 (human, bovine, mouse, rat)
  • H-5468: (Ala13)-Apelin-13 (human, bovine, mouse, rat)
  • H-4894: (Tyr0)-Apelin-13 (human, bovine, mouse, rat)
  • H-5806: Apelin-12 (human, bovine, mouse, rat)

Radiolabeled peptides

  • H-6482 ([125I]-Tyr)-Apelin-17 (human, bovine, mouse, rat)

Immunology products

  • T-4824: Apelin-17 (human, bovine, mouse, rat) – Purified Antiserum – IgG, Host: Rabbit
  • T-4823: Apelin-17 (human, bovine, mouse, rat) – Diluted Antiserum for RIA, Host: Rabbit
  • T-4825: Apelin-17 (human, bovine, mouse, rat) – Undiluted Antiserum for Immunohistochemistry, Host: Rabbit
  • S-2253: Apelin-17 (human, bovine, mouse, rat) – RIA Kit, Host: Rabbit
  • T-2304: Apelin Receptor (mouse, rat) – Polyclonal

For additional information on these and many other biologically active peptides and immunology products, please see our catalogue or homepage.