The effect of PAR-1 agonist peptide on RBC velocity (VRBC) of XRITC-labeled sickle RBCs injected into mouse recipients expected to have different levels of endothelial P-selectin expression. Results are described as VRBC in C57BL/6 (control), P-selectin knock-out (P-sel k/o), and sickle cell mice. (A) Average VRBC of labeled sickle RBCs in control (n = 5), P-selectin knock-out (n = 5), and sickle cell mice (n = 4) 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) slowing due to PAR-1 agonist peptide (PAR-1ap) suffusion. Each plot represents a single representative experiment. (C) A single frame captured of labeled sickle RBCs in PAR-1 agonist peptide-treated vessels. Sickle RBCs moving rapidly (*) and rolling slowly (#) are indicated.
