RCAN1 and cardiac hypertrophy: To further investigate the altered hypertrophic response in Trpm4cKO mice, we performed qPCR experiments to evaluate the expression level of known cardiac hypertrophy “marker” genes, i.e., α-actin, myosin heavy chain beta (MYH7), atrial natriuretic peptide (ANP), Rcan1 (a negative regulator of calcineurin of which the transcription is highly dependent on calcineurin–NFAT activation) and the α1H subunit of voltage-gated T-type Ca2+ channel (CACNA1H), which is also known to be re-expressed upon cardiac hypertrophy [3].