Figure 1.

Methods; venous occlusion plethysmography Acetylcholine was infused intra-arterially at 7.5, 15 and 30 g/min for 5 minutes for each dose level and forearm blood flow was measured during the last 2 minutes of each dose. Forearm blood flow response to acetylcholine was assessed during the infusion of dextrose solution (stage 1), intra-arterial infusion of vitamin C (stage 2) and intra-arterial co-infusion of vitamin C and L-NMMA (NG-monomethyl-L-arginine (stage 3).