ERBB2 and diabetes mellitus: Western blot analyses showed for the first time that diabetes led to enhanced ErbB2 expression and phosphorylation at multiple tyrosine residues (Y1221/1222, Y1248 and Y877) in the mesenteric vascular bed that was effectively blocked by chronic AG825 treatment of animals (Figure 2) confirming the importance of ErbB2 activation in diabetes-induced vascular dysfunction.