Calcitonin gene-related peptide (CGRP) and hypertrophy of cardiomyocytes

We studied whether calcitonin gene-related peptide (CGRP), a neuropeptide secreted from the sensory nervous supply to the myocardium, induces hypertrophy of cardiomyocytes in culture. CGRP increased the cell surface area of neonatal rat cardiomyocytes; the surface area of the cells was almost doubled by treatment with CGRP for 48 h. Furthermore, CGRP up-regulated mRNA expression for skeletal alpha-actin and atrial natriuretic peptides, which are genetic markers for cardiac hypertrophy. These results indicate that CGRP is a potent hypertrophic factor for cardiomyocytes.