RAPGEF3 and cardiac hypertrophy: In support of a role of Epac1 in the progression of cardiac hypertrophy, ectopic overexpression of Epac1 or direct activation of Epac1 with the cAMP analogue, 8-pCPT-cAMP induced various features of cardiac hypertrophy in rat neonatal cardiac myocytes, including myofibrillogenesis, increased cell surface area, protein synthesis, and expression of the atrial natriuretic peptide (ANF) [54].