Antithrombotic and vasorelaxant properties of a novel synthetic RGD peptide containing nitric oxide.

We have developed a novel synthetic peptide containing both the antiadhesive Arg-Gly-Asp (RGD) amino acid sequence and a nitric oxide (NO) moiety well known for its vasorelaxant properties. The main objective of this study was to determine whether this hybrid molecule is concurrently effective with regard to antithrombotic and vasorelaxation actions. Studies of in vitro platelet adhesion and of in vivo platelet thrombus formation in the rat demonstrated that the RGD-NO peptide increased the antithrombotic characteristics of the RGD peptide alone. The RGD-NO peptide also caused relaxation of rat aortic rings, while the RGD peptide did not induce relaxation. These characteristics of Ac-RGDC-SNO suggest that this or similar compounds may have potential as effective antithrombotic agents in coronary and peripheral artery disorders.