Figure 5 Infused (solid line) and non‐infused (dashed line) forearm blood flow (panel A) and estimated net release of tissue plasminogen activator (t‐PA) antigen (panel B) at baseline, during sildenafil (•) and matched placebo (○) infusion (shaded box), and subsequently with intrabrachial substance P (2, 4, 8 pmol/min) in patients with CHD. p < 0.01 analysis of variance for all, dose response for infused arm FBF and net t‐PA release.