Antithrombotic properties of L-cysteine, N-(mercaptoacetyl)-D-Tyr-Arg-Gly-Asp-sulfoxide (G4120) in a hamster platelet-rich femoral vein thrombosis model.

Abstract

Platelet aggregation plays an important role in the pathogenesis in arterial thrombotic disorders. The binding of fibrinogen via the Arg-Gly-Asp (RGD) recognition sequence to the platelet glycoprotein IIb/IIIa (GPIIb/IIIa) receptor is an essential step of platelet aggregation induced by various physiologic agonists, and RGD-containing peptides that bind to the GPIIb/IIIa receptor inhibit thrombus formation in vivo. L-cysteine, N-(mercaptoacetyl)D-tyrosyl-L-arginylglycyl-L alpha-aspartyl-cyclic (1----5)-sulfide, 5-oxide (G4120), a cyclic RGD-containing synthetic pentapeptide, inhibits adenosine diphosphate (ADP)-induced platelet aggregation with 50% inhibition (IC50) at a concentration of 0.05 microgram/mL in human plasma, 0.12 microgram/mL in hamster plasma, and 11 micrograms/mL in rat plasma. Corresponding values for the linear tetrapeptide Arg-Gly-Asp-Phe (RGDF) were 7 and 100 micrograms/mL in human and hamster plasma. The antithrombotic effects of G4120 and RGDF were evaluated in a hamster model consisting of a mural platelet-rich femoral vein thrombus induced by standardized endothelial cell damage. Bolus intravenous injection of G4120 was followed by a biphasic disappearance of G4120 from plasma with t1/2 alpha of 3.7 minutes and t1/2 beta of 63 minutes, corresponding to a plasma clearance of 5.2 +/- 0.68 mL/min. Bolus intravenous injection of G4120 inhibited ex vivo platelet aggregation with 0.5 mumol/L ADP and in vivo thrombus formation in a dose-dependent manner, with ID50 of 11 and 11 micrograms/kg, respectively. Bolus injection of RGDF inhibited in vivo thrombus formation; 43% inhibition was obtained at a dose of 30 mg/kg. Thus, this hamster platelet-rich femoral vein thrombosis model may be useful for the investigation of the antithrombotic properties of platelet GPIIb/IIIa antagonistic peptides. The cyclic synthetic peptide G4120 appears to have a very potent antithrombotic activity in vivo.

• Authors: Y Imura, J M Stassen, S Bunting, F Stockmans, D Collen
• Journal: Blood (Blood) Vol. 80 Issue 5 Pg. 1247-53 (Sep 01 1992) ISSN: 0006-4971 [Print] United States
• PMID: 1515641 (Publication Type: Journal Article)

Chemical References

• Fibrinolytic Agents
• Oligopeptides
• Peptides, Cyclic
• Platelet Aggregation Inhibitors
• Platelet Membrane Glycoproteins
• Sulfoxides
• G 4120
• arginyl-glycyl-aspartic acid

Topics

• Amino Acid Sequence
• Animals
• Cricetinae
• Disease Models, Animal
• Dogs
• Femoral Vein
• Fibrinolytic Agents (pharmacology)
• Humans
• Male
• Molecular Sequence Data
• Oligopeptides (pharmacology)
• Peptides, Cyclic (pharmacokinetics, pharmacology)
• Platelet Aggregation (drug effects)
• Platelet Aggregation Inhibitors (pharmacology)
• Platelet Membrane Glycoproteins (antagonists & inhibitors)
• Rats
• Sulfoxides (pharmacokinetics, pharmacology)
• Thrombosis (drug therapy)