Figure 4: Mean concentration- (log mg/mL) relaxation (%) curves for Suxiao Jiuxin Pill (−2~1.25 log mg/mL) in endothelium-denuded ( ; (a)) and L-NNA (300 μM, ; (b)) pretreated IMA rings precontracted with 40 mM KCl. Endothelium-intact IMA rings taken from the same patient were studied as control. Values are expressed as mean ± SEM. , , compared with endothelium-intact control group. Suxiao: Suxiao Jiuxin Pill; Endo-denuded: endothelium-denuded.