Isoproterenol Induces Vascular Oxidative Stress and Endothelial Dysfunction via a Giα-Coupled β2-Adrenoceptor Signaling Pathway
Figure 5
Inhibition of Giα protein or ERK1/2 activation reversed hypercontractility to phenylephrine induced by β-AR overactivation in aorta of wild-type, but not in β2KO mice.
Effect of pertussis toxin (PTx, 4 μM) and PD98,059 (1 μM) on the concentration-response curves to phenylephrine in aortic rings of wild-type (WT) (A, D) and β2KO (B, E) mice treated for 7 days with vehicle or isoproterenol (ISO). The contraction response is expressed as a % of the contraction to KCl (125 mM). Bar graphs show differences in the area under the concentration-response curve (AUC) in the presence or absence of PTx (C) or PD98,059 (F) in WT and β2KO mice treated or not with ISO. Values are presented as the mean ± SEM. The number of animals used in each group is indicated in parenthesis. Significance was assessed using a 2-way ANOVA: +p<0.05 vs. WT ISO; *p<0.05 vs. WT.