Figure 2.

Comparison of L-arginine and NO derivative concentrations, and the vascular endothelial function between the normal controls and the patient. (a) Serum L-arginine concentration (nmol/ml) in normal controls (n = 10; control A) and in the patient (three independent determinations) before (control A, patient) and after (control A [Arg], patient [Arg]) L-arginine infusion. Values represented are the mean ± SD. A statistical analysis was determined using Welch’s t test. (b) Serum NO derivative concentrations (μM) in normal controls (n = 10; control A) and the patient (three independent determinations) before (control A, patient) and after (control A [Arg], patient [Arg]) an L-arginine infusion. Values shown are the mean ± SD. A statistical analysis among the four groups was performed using the Kruskal-Wallis test (P = 0.001), followed by Scheffé’s test for multiple comparisons to allow pairwise testing for significant differences between the groups. (c) Percent increase in endothelium-dependent vasodilation (EDV) in normal controls (n = 10; control A) and the patient (three independent determinations) before (control A, patient) and after (control A [Arg], patient [Arg]) an L-arginine infusion. Values represented are the mean ± SD. A statistical analysis among the four groups was performed by the Kruskal-Wallis test (P = 0.049), followed by Scheffé’s test for multiple comparisons to enable pairwise testing for significant differences between the groups. (d) Percent increase in EIV after sublingual nitroglycerin (300 mg) in normal controls (n = 10; control B) and in the patient (five independent determinations). Values represented are mean ± SD. A statistical analysis was determined using the Welch’s t test.