NADPH derived superoxide is involved in the endothelial dysfunction induced by acute amylin treatment in mesenteric arteries of control rats.

<p>The impact of the superoxide scavenger, superoxide dismutase (SOD, 100 U/ml) (A), and the hydrogen peroxide (H₂O₂) scavenger (catalase, 600 U/ml) (B) on the effects of acute r-amylin treatment (40 pM) on endothelium-dependent relaxation induced by acetylcholine (ACh; 1 nM to 10 μM) in isolated mesenteric arteries from control rats (CR) is shown. The influence of the NADPH oxidase inhibitor, VAS 2870 (10 μM) on relaxant response elicited by acetylcholine (ACh; 1 nM to 10 μM) in mesenteric arteries from CR exposed to acute amylin (Panel C) is also reported. (n) Indicates the number of vascular segments used for determinations. Data are expressed as mean±SE of the remaining contraction induced by norepinephrine (NE). ** Indicates p < 0.001; *** Indicates p < 0.0001 versus CR, ††† indicates p < 0.0001 versus CR plus amylin (40 pM) by two-factors ANOVA test.