An abnormal Ca(2+) response in mutant sarcomere protein-mediated familial hypertrophic cardiomyopathy

J Clin Invest. 2000 Dec;106(11):1351-9. doi: 10.1172/JCI11093.


Dominant-negative sarcomere protein gene mutations cause familial hypertrophic cardiomyopathy (FHC), a disease characterized by left-ventricular hypertrophy, angina, and dyspnea that can result in sudden death. We report here that a murine model of FHC bearing a cardiac myosin heavy-chain gene missense mutation (alphaMHC(403/+)), when treated with calcineurin inhibitors or a K(+)-channel agonist, developed accentuated hypertrophy, worsened histopathology, and was at risk for early death. Despite distinct pharmacologic targets, each agent augmented diastolic Ca(2+) concentrations in wild-type cardiac myocytes; alphaMHC(403/+) myocytes failed to respond. Pretreatment with a Ca(2+)-channel antagonist abrogated diastolic Ca(2+) changes in wild-type myocytes and prevented the exaggerated hypertrophic response of treated alphaMHC(403/+) mice. We conclude that FHC-causing sarcomere protein gene mutations cause abnormal Ca(2+) responses that initiate a hypertrophic response. These data define an important Ca(2+)-dependent step in the pathway by which mutant sarcomere proteins trigger myocyte growth and remodel the heart, provide definitive evidence that environment influences progression of FHC, and suggest a rational therapeutic approach to this prevalent human disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Calcineurin Inhibitors
  • Calcium / metabolism*
  • Cardiomyopathy, Hypertrophic / drug therapy
  • Cardiomyopathy, Hypertrophic / genetics
  • Cardiomyopathy, Hypertrophic / metabolism*
  • Cyclosporine / pharmacology
  • Echocardiography
  • Enzyme Inhibitors / pharmacology
  • Heart Ventricles / drug effects
  • Heart Ventricles / metabolism
  • Heart Ventricles / pathology
  • Mice
  • Minoxidil / pharmacology
  • Mutation
  • Myosin Heavy Chains / genetics*
  • Sarcomeres / chemistry
  • Survival Analysis
  • Tacrolimus / pharmacology


  • Calcineurin Inhibitors
  • Enzyme Inhibitors
  • Minoxidil
  • Cyclosporine
  • Myosin Heavy Chains
  • Calcium
  • Tacrolimus