The effect of pretreatment with anti-P-selectin mAb (anti-P-sel) and unfractionated heparin (UFH) on PAR-1 agonist peptide-reduced RBC velocity (VRBC) of XRITC-labeled sickle RBCs injected into C57BL/6 (control) mice. Results described are VRBC. (A) Average velocities of labeled sickle RBCs (VRBC) in control-(n = 5), anti-P-selectin-(n = 3), or UFH-treated (n = 6) mice before (-) and 2 minutes after (+) PAR-1 agonist peptide suffusion. The error bars indicate the standard error of the mean. (B) Real-time course plots of RBC velocity (VRBC) changes induced by PAR-1 agonist peptide (PAR-1ap) suffusion. Each plot represents a single representative experiment. The representative time course for PAR-1 agonist peptide alone is consistent with the overall findings in which slowing of flow always ensued within 2 minutes and stoppage of flow occurred within 4 minutes.
