Carnitine palmitoyltransferase in patients with cardiac ischemia due to atherosclerotic coronary artery disease and in patients with idiopathic dilated cardiomyopathy.
Cardiac ischemia is associated with an impairment in long-chain fatty acid metabolism. We studied carnitine palmitoyltransferase (CPT) in left ventricular biopsies of 6 transplant recipients with ischemia due to atherosclerosis, 4 patients with dilated cardiomyopathy, and 5 donor hearts. Total CPT activity was not significantly different between the three groups (7.9 +/- 3; 6.7 +/- 2, and 8 +/- 3 nmol/min/mg noncollagenous protein). Residual CPT activity after inhibition by malonyl-CoA (0.4 mM) was 38 +/- 11, 36 +/- 5 and 38 +/- 7%. There were no difference in IC50 values. Residual CPT activity after the addition of the detergent Triton X-100 (0.5%) was 58 +/- 17, 54 +/- 2 and 50 +/- 8% (nonsignificant). Our results suggest that (i) total CPT activity and (ii) the sensitivity of the interaction of CPT I with its regulator malonyl-CoA are not affected by cardiac ischemia, and (iii) the ratio of CPT I to CPT II is not altered in cardiac ischemia.
Maurer
I
I
Department of Neurology, Friedrich Wilhelm University, Bonn, Germany.
Zierz
S
S
D000328:Adult; D015415:Biomarkers; D001706:Biopsy; D002311:Cardiomyopathy, Dilated / Q000201:enzymology* / Q000473:pathology / Q000601:surgery; D002334:Carnitine O-Palmitoyltransferase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D002462:Cell Membrane / Q000201:enzymology; D003324:Coronary Artery Disease / Q000150:complications / Q000201:enzymology / Q000473:pathology; D016027:Heart Transplantation; D006352:Heart Ventricles / Q000201:enzymology* / Q000473:pathology; D006801:Humans; D008297:Male; D008316:Malonyl Coenzyme A / Q000494:pharmacology; D008875:Middle Aged; D008929:Mitochondria, Heart / Q000201:enzymology; D017202:Myocardial Ischemia / Q000201:enzymology* / Q000209:etiology / Q000473:pathology; D014019:Tissue Donors
D015415:Biomarkers; D008316:Malonyl Coenzyme A; D002334:Carnitine O-Palmitoyltransferase