The snake venom peptide sarafotoxin S6b inhibits repetitive platelet thrombus formation in the stenosed canine coronary artery.

Various snake venom peptides have been extensively evaluated for use as antithrombotic agents. Recently, it was determined that the snake venom peptide sarafotoxin S6b (S6b) is structurally similar to the potent vasoactive hormone endothelin-1 (ET-1), which has been shown to inhibit agonist-induced platelet aggregation. The potential in vivo antithrombotic activity of S6b was compared with that of ET-1, a much more potent pressor agent than S6b, by evaluating the effects of S6b and ET-1 (0.5 μg/kg i.v.) on repetitive platelet thrombus formation (RPTF) in the stenosed canine circumflex coronary artery. In this model platelets adhere to the damaged vessel wall near a mechanically produced stenosis