Fig. 6: Nitrite consumption is increased by chemical hypoxia in isolated thoracodorsal vessels.
Nitrite (NO2–) (a), nitrate, (NO3–) (b), and summed NO2– and NO3– species (c) were measured after isolated vessels were incubated with sodium dithionite (Na2S2O4). Wild-type thoracodorsal vessels treated with Na2S2O4 or buffer deoxygenated with N2 gas showed decreased intracellular NO2– when compared to vessels treated with water (H2O) (leftmost group). All experimental genotypes and their littermate controls were treated with Na2S2O4, and the experimental genotypes were treated with H2O as a vehicle control (cross-hatched bars). Vessels from both global Hba1–/– and EC Hba1Δ/Δ mice showed higher levels of NO2– and lower NO3– levels when compared to those of littermate controls with chemical hypoxia, whereas the total amount of NO2– and NO3– did not differ from controls. In this study, n = 7 WT vessels were treated with H2O; n = 6 WT vessels were treated with Na2S2O4; and n = 5 WT vessels were treated with N2 gas-treated buffer. For these experiments, n = 5 Hba1+/+ mice, n = 5 Hba1–/– mice, n = 6 Hba1fl/fl mice, n = 6 EC Hba1Δ/Δ mice, n = 4 Hba1WT/WT mice, and n = 4 Hba1WT/Δ36–39 mice were used. Results for littermates were compared with one-sided t tests. Bar graphs are centered on mean with error bars denoting standard error. Source data are provided in the Source data file.
