Journal
JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY
Volume 22, Issue 3, Pages 316-324Publisher
WILEY-BLACKWELL
DOI: 10.1111/j.1540-8167.2010.01877.x
Keywords
antiarrhythmia agents; calcium; calsequestrin-2; CPVT; mouse model; sudden death
Categories
Funding
- HHMI
- Machiah Foundation
Ask authors/readers for more resources
Method and results: CPVT mouse models that lack CASQ2 were treated with Ca2+-channel inhibitors, beta-adrenergic inhibitors, or Mg2+. Treatment effects on ventricular arrhythmia, sarcoplasmic reticulum (SR) protein expression and Ca2+ transients of isolated myocytes were assessed. Each study agent reduced the frequency of stress-induced ventricular arrhythmia in mutant mice. The Ca2+ channel blocker verapamil was most efficacious and completely prevented arrhythmia in 85% of mice. Verapamil significantly increased the SR Ca2+ content in mutant myocytes, diminished diastolic Ca2+ overload, increased systolic Ca2+ amplitude, and prevented Ca2+ oscillations in stressed mutant myocytes. Conclusions: Ca2+ channel inhibition by verapamil rectified abnormal calcium handling in CPVT myocytes and prevented ventricular arrhythmias. Verapamil-induced partial normalization of SR Ca2+ content in mutant myocytes implicates CASQ2 as modulator of RyR2 activity, rather than or in addition to, Ca2+ buffer protein. Agents such as verapamil that attenuate cardiomyocyte calcium overload are appropriate for assessing clinical efficacy in human CPVT. (J Cardiovasc Electrophysiol, Vol. 22, pp. 316-324, March 2011).
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available