A novel anti-hypertensive peptide derived from ovalbumin induces nitric oxide-mediated vasorelaxation in an isolated SHR mesenteric artery

In this report, we deal with the isolation of a novel vasorelaxing peptide from a chymotryptic digest of ovalbumin and its vasorelaxing activities. This peptide is composed of Arg-Ala-Asp-His-Pro-Phe (RADHPF) in its sequence, corresponding to residues 359-364 of ovalbumin, This peptide (30-300 mu M) exerted a dose-dependent vasodilation in an isolated mesenteric artery from a spontaneously hypertensive rat which was preconstricted by phenylephrine, besides the relaxation being endothelium-dependent. It is noteworthy that the nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester inhibited this relaxation, implying involvement of nitric oxide in its mechanism of action. Following oral administration of RADHPF at a dose of 10 mg/kg, the systolic blood pressure in a spontaneously hypertensive rat was significantly lowered. (C) 1999 Federation of European Biochemical Societies.