RVD Hpα

RVD-Hpα is an endogenous neuropeptide found in human and mammalian brain, which was originally proposed to act as a selective agonist for the CB₁ cannabinoid receptor. It is a 12-amino acid polypeptide having the amino acid sequence Arg-Val-Asp-Pro-Val-Asn-Phe-Lys-Leu-Leu-Ser-His and is an N-terminal extended form of hemopressin, a 9-AA polypeptide derived from the α₁ subunit of hemoglobin which has previously been shown to act as a CB₁ inverse agonist. All three polypeptides have been isolated from various mammalian species, with RVD-Hpα being one of the more abundant neuropeptides expressed in mouse brain, and these neuropeptides represent a new avenue for cannabinoid research distinct from the previously known endogenous lipid-derived cannabinoid agonists such as anandamide. Recently it was shown that RVD-Hpα (also called Pepcan-12) is a potent negative allosteric modulator at CB₁ receptors, together with other newly described N-terminally extended peptides (pepcans).