Effects of Monoclonal Antibody to P-Selectin and Analogue of Sialyl Lewis X on Cyclic Flow Variations in Stenosed and Endothelium-Injured Canine Coronary Arteries

Abstract
BackgroundA fundamental role of cell adhesion molecules is implicated in the disease processes of acute coronary syndromes. We have shown an increase in the soluble form of P-selectin in these syndromes, suggesting the important interaction between P-selectin and sialyl Lewis X (SLeX) for the pathophysiology of these syndromes. To further test this, we examined the effects of a monoclonal antibody against P-selectin (PB1.3) and a carbohydrate analogue of SLeX(SLeX-OS) on cyclic flow variations (CFVs) in stenosed and endothelium-injured canine coronary arteries.Methods and ResultsAnesthetized, open-chest dogs (n=48) were divided into six groups after CFVs were established. Dogs received intravenous normal saline, PB1.3 (1 mg/kg bolus), a low dose (5 mg/kg bolus) or a high dose (40 mg/kg bolus) of SLeX-OS followed by an infusion (5 mg·kg−1·h−1) for 60 minutes, a combination of PB1.3 and SLeX-OS (low dose), or a combination of a nonblocking antibody against P-selectin (PNB1.6, 1 mg/kg) and SLeX-OS (low dose). Although saline, PB1.3, SLeX-OS (low dose), and the combination of PNB1.6 and SLeX-OS (low dose) did not affect CFVs, the high dose of SLeX-OS and the combination of PB1.3 and SLeX-OS (low dose) significantly reduced CFVs.ConclusionsThese findings indicate that the high dose of SLeX-OS and the combination of PB1.3 and the low dose of SLeX-OS provide protection against CFVs. Thus, the adhesive interaction between P-selectin and SLeXmay play an important role in mediating CFVs in this model.