% change in diameter from baseline in arterioles in responses to the endothelium-dependent vasodilator, acetylcholine (ACh) (A) or the endothelium-independent vasodilator, papaverine (papav) (B). The ratio between papav and ACh responses is depicted in panel C. WT, P-sel−/− or L-sel−/− mice received mock inoculum or mCMV, and were either kept on ND, or switched to HC at 5 wks p.i., until observation at 11 wks p.i. Separate WT mCMV groups were treated with anti-P-selectin antibody (+P-sel Ab) or an isotype-matched control antibody (+P-sel iso Ab) 24 h prior to the experiment. * P<0.05 vs. both WT Mock groups; ** P<0.005 vs. both WT Mock groups; # P<0.005 vs. WT mCMV-ND and WT mCMV-ND+P-sel iso Ab; ^ P<0.005 vs. WT mCMV-HC; ^^ P<0.0005 vs. WT mCMV-HC; † P<0.01 vs. WT mCMV-HC+P-sel iso Ab; § P<0.005 vs. L-sel−/− Mock-ND.