VCAM1 and endothelial dysfunction: For endothelial dysfunction measured using Ach-induced iontophoresis, eGFR's indirect effect mediated by iPTH and VCAM-1 was significant, as opposed to eGFR's direct effect (Figures 2E,F), and iPTH significantly mediated the effect of VCAM-1 on endothelial dysfunction (Figure 2G).