Fig. 7.

A: total proteins of mesenteric arteries from young and aged mice were analyzed by Western blotting with anti-nitrotyrosine antibody. The bottom panel is the same blot probed with β-actin as a loading control. B: summary data of densitometry of nitrotyrosine. Data are means of two Western blots. The amounts of nitrotyrosine were normalized to the expression of actin. *Significant differences from young mice, P < 0.05. C: immunostaining of nitrotyrosine and eNOS in sections of mesenteric arteries of young and aged mice. I, Cy3-labeled nitrotyrosine. II, FITC-labeled eNOS. III, merged images of I and II. IV, DAPI-stained nuclei. V, profile of vessel sections. DIC, differential interference contrast. D: eNOS protein was immunoprecipitated by monoclonal eNOS antibody. The immuno-complexes were then subjected to SDS-PAGE, followed by Western blot analysis with anti-nitrotyrosine antibody. The bottom panel indicates that equal amounts of eNOS were loaded. IB, immunoblotting; IP, immunoprecipitation.