HIF1A and heart failure: Phosphorylation of CX43 is important for the functionality of this protein in gap junctions [42] and reduced levels of phosphorylated CX43 have been shown to correlate with worsened heart function in the heart failure model [43].Thus, decreased levels of phosphorylated CX43 in the heart may negatively influence the myocardial function of Hif1a+/− mice from diabetic pregnancies.