Glycolysis in heart failure: a 31P-NMR and surface fluorometry study.
Glycolysis is slow in the heart, especially in the cardiomyopathic heart. Glycolysis is partially rate-limited by phosphofructokinase (PFK), an enzyme which is inhibited by calcium (Ca2+)i and hydrogen ions (H+)i and activated by cAMP. (H+)i and (Ca2+)i are augmented in cardiomyopathy. With glucose as the only substrate (NADH)/(NAD) the phosphorylation potential and developed pressure were significantly lower, and concentrations of phosphomonoester sugars and hydrogen ions (H+)i were significantly higher in isolated cardiomyopathic hearts as compared to healthy hamster hearts. Pyruvate lowered diastolic (Ca2+)i in cardiomyopathic hamster hearts. With pyruvate as the substrate (NADH)/(NAD), the phosphorylation potential and developed pressure increased significantly and concentrations of phosphomonoester sugars (PME), (H+)i and diastolic (Ca2+)i decreased significantly in myopathic hamster hearts. The results suggest that late heart failure in the myopathic hamster is associated with calcium and/or hydrogen ion-induced inhibition of glycolysis.
Auffermann
W
W
Department of Medicine, University of California, San Francisco.
Wu
S T
ST
Parmley
W W
WW
Wikman-Coffelt
J
J
D000818:Animals; D002303:Cardiac Output, Low / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D009202:Cardiomyopathies / Q000150:complications / Q000235:genetics; D006224:Cricetinae; D005456:Fluorescent Dyes; D005470:Fluorometry / Q000379:methods*; D005947:Glucose / Q000378:metabolism; D006019:Glycolysis; D007211:Indoles; D009682:Magnetic Resonance Spectroscopy; D008647:Mesocricetus; D009206:Myocardium / Q000378:metabolism / Q000473:pathology; D009243:NAD / Q000378:metabolism; D010758:Phosphorus; D011773:Pyruvates / Q000378:metabolism; D012016:Reference Values
D005456:Fluorescent Dyes; D007211:Indoles; D011773:Pyruvates; D009243:NAD; D010758:Phosphorus; D005947:Glucose; C048960:indo-1