ERBB2 and diabetes mellitus: Figure 4 provided evidence for the likely dimerization or EGFR and erbB2 in normal and diabetic hearts. Importantly as implied by the cardiac function studies, compared to normal animals diabetes led to decreased levels of EGFR/erbB2 dimerization in the heart that was further reduced upon chronic treatment of animals with either AG1478 or AG825. The reduced dimerization may partly be explained by reduced expression of the two receptors in diabetic hearts as seen in Figures 1 and 2.