CALCITONIN-GENE-RELATED PEPTIDE (CGRP) AND HYPERTROPHY OF CARDIOMYOCYTES

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