A-D. Comparison of different PAR-APs in inducing mouse bladder inflammation. Characteristic photomicrographs of bladders removed from female C57BL6 mice that received instillation of (A = control peptide; B = PAR1-AP; C = PAR2-AP, and D = PAR4-AP). All peptides were at the concentration of 10 μM and bladders were removed 24 hours after challenge. Of note, absence of inflammation following instillation with control peptide (A), submucosal PMN infiltrate induced by PAR1-AP (B), modest perivascular infiltration in response to PAR2-AP (C), and overwhelming PMN infiltration in response to PAR4-AP (D). Magnifications: A, B, C, and D = ×200.