Altered coenzyme A and carnitine metabolism in pressure-overload hypertrophied hearts

Changes in the total content and acylation state of coenzyme A (CoA) and carnitine in the heart result in alterations in fatty acid metabolism that may be associated with ventricular dysfunction. The present study was undertaken to determine whether abnormal myocardial CoA and carnitine metabolism occur in pressure-overload hypertrophy and congestive heart failure. Right ventricular hypertrophy was induced in cats by pulmonary artery (PA) banding. Total tissue CoA was reduced by 50% in the hypertrophied right ventricle and 25% in the nonhypertrophied left ventricle of PA-banded cats in the presence or absence of heart failure. No alterations were observed in long-chain fatty acyl CoA levels in either ventricle of PA-banded cats. In addition, a 20% reduction in total CoA was also observed in hypertrophied hearts of rats subjected to aortic banding. Although the CoA content was reduced in hypertrophied cat hearts, myocardial tissue levels of its precursor, pantothenic acid, were unaltered. Total tissue carnitine and long-chain fatty acyl-carnitine levels were unchanged in both ventricles of PA-banded cats; however, total carnitine was reduced by 25% in hypertrophied rat hearts. This study establishes a marked reduction in myocardial CoA content in pressure-overload hypertrophy.