Fig. 1: Different NO-ferroheme preparations potently relax blood vessels.
a–d, EPR spectra (X band; 77K) of different NO-ferroheme preparations together with ex vivo vasorelaxation responses of aortic rings to increasing concentrations of (NO-ferroheme)4-Hb (n = 14) (a), NO-ferroheme-Mb (n = 31) (b), NO-ferroheme-BSA (n = 4) (c) and NO-ferroheme-l-Cys (n = 27) (d), using the myograph system in the presence of 0.1 mM L-NAME. n represents the number of mouse aortic rings used in different myograph chambers. Vasorelaxation responses are shown as percent of PE-induced plateau, and the data are presented as mean ± s.e.m. Half maximal EC50 values were calculated using least squares nonlinear regression analysis and are presented as log and absolute values with a 95% CI. CI, confidence interval; EC50, effective concentration; PE, phenylephrine.
