Figure 5.
Summary of the effect of flow on inhibition of vasodilation by free Hb and RBCs from Figs. 1–4. The presence of flow reduced the inhibitory effect of RBCs (50–60% hematocrit) on NO-mediated vessel dilation [+, P < 0.05, serotonin (5-HT) versus flow, ΔP = 60 cm H2O]. In contrast, flow did not change the effect of free Hb. Free Hb (10 μM) effectively inhibited NO-mediated dilation in response to either serotonin (0.1 μM) or shear stress (ΔP = 60 cm H2O), but RBCs (50–60% hematocrit) had significantly less effect. ∗, P < 0.05, RBCs versus free Hb.