First 11 pages of thesis. - OPUS - Universität Würzburg

3.0 Results
3.1 eNOS is a significant source of vascular wall nitric oxide
production and circulating nitric oxide
Quantitation of baseline nitric oxide production in the vasculature is a
challenging task, due to the radical’s short half-life and very low concentrations
of bioavailable nitric oxide. We used ESR, a method of highest sensitivity and
specificity, to measure vascular nitric oxide production and circulating nitric
oxide levels in blood samples. Spin trapping of nitric oxide with colloidal Fe-
(DETC)2 was used to measure baseline nitric oxide production of the vessel
wall. This is considered a very specific method for detection of nitric oxide, since
the Fe-(DETC)2 bound to nitric oxide gives rise to a specific triplet hyperfine
nitric oxide-Fe-(DETC)2 peak, whereas Fe-(DETC)2 alone does not give any
signal (Figure 8a). Our experiments show that the baseline nitric oxide
production of the vessel wall is significantly lower in apoE/eNOS dko (920±287
AU/µg protein, n=12) than in apoE ko mice (2554±195 AU/µg protein, n=14,
p