Low oxygen tensions increase the efficiency of vasodilation stimulated by structurally and mechanistically distinct nitrosovasodilators
Nitrosovasodilator . | Fold decrease in EC50 for relaxation at low oxygen tensions . |
|---|---|
| SNOoxyHb | 3.7 ± 1.1 |
| SNOmetHb | 2.91 ± 1.3 |
| GSNO | 3.2 ± 0.8 |
| DeaNonoate | 14.7 ± 1.1 |
| Angelis salt | 3.3 |
Nitrosovasodilator . | Fold decrease in EC50 for relaxation at low oxygen tensions . |
|---|---|
| SNOoxyHb | 3.7 ± 1.1 |
| SNOmetHb | 2.91 ± 1.3 |
| GSNO | 3.2 ± 0.8 |
| DeaNonoate | 14.7 ± 1.1 |
| Angelis salt | 3.3 |
Concentration-dependent relaxation responses for SNOoxyHb, SNOmetHb, GSNO (0-100 nM), DeaNonoate (0-25 nM), and Angelis salt (AS, 0-200 nM) were determined as described in “Materials and methods” under either low oxygen or high oxygen conditions. For SNOHb, concentrations ranged from 10-300 nM heme with 1 SNO per tetramer. Fold changes in EC50 for relaxation were thus determined. Values represent the fold decrease in EC50 under hypoxic conditions relative to hyperoxic conditions. Data represent mean ± SEM (n = 3).