Figure 1.

ESR measurements of vascular NO production: Quantification of aortic NO production using Fe-(DETC)₂ spin trap. Signal represents NO production from vessel rings over a one hour incubation period. ApoE^−/− mice produced higher NO concentrations compared with C57Bl6 mice of both sexes (females: n = 6 vs. n = 5 *P < 0.05; males: n = 8 vs. n = 7, P < 0.05). Genetic deletion of iNOS in apoE^−/−/iNOS^−/− mice reduced NO formation to the levels of C57Bl6 mice. NO production was higher in female apoE^−/− (n = 6) and apoE^−/−/iNOS^−/− (n = 13 ± SE) animals compared with males (apoE^−/−: n = 8 and apoE^−/−/iNOS^−/−: n = 13) within each genotype. **P ≤ 0.01. All values are expressed as mean ± SE.