Fig. 5.

NO measured in the gas phase of a membrane gas exchanger perfused with a liquid phase of diluted blood and a gas phase supplied with nitrogen. A: introduction of the NO donor 1-(hydroxy-NNO-azoxy)-L-proline (PROLI-NO) into a liquid phase of PBS provided significant increases of NO in the gas phase at all concentrations of PROLI-NO infused. Concentrations of NO as low as 0.1 μM in the liquid phase result in gas phase NO concentrations of 93 ± 5 ppb. B: during perfusion with diluted blood (hematocrit 4–6%), no detectable NO increases were measured until nitrite concentrations were increased to 10 mM (not shown), and there were no differences between human and sheep blood. Note that NO scales differ by a factor of 100. Means are ± SE.