[Mechanisms of the regulation of muscle energy metabolism on oxidation of glucose and fatty acids. A mathematical model].
A mathematical model was used to study the role of various allosteric regulatory mechanisms in the oxidation of glucose and fatty acids by muscle energy metabolism. A large number of such mechanisms were shown to be involved in simultaneous oxidation of both substrates: glycolysis is regulated by the ATP/ADP ratio at the phosphofructokinase (PFK) step; the control over pyruvate dehydrogenase is exercised by the NADHm/NADm+ and CoAsAc/CoAsH ratios as well as by the level of pyruvate; the Krebs cycle is regulated by oxaloacetate and citrate concentrations in the citrate synthase reaction and by the ATP/ADP and NADHm/NADm+ ratios in the isocitrate dehydrogenase reaction. The inhibition of PFK and pyruvate dehydrogenase by excess of CoAsAcyl as well as the inhibition of PFK by citrate are additional equivalent regulatory mechanisms. When glucose alone is oxidized, the levels of citrate, CoAsAcyl, NADHm and CoAsAc decrease drastically within the whole range of physiological ATPase loads; the only regulating factors that remain efficient are the ATP/ADP ratio in glycolysis, the level of pyruvate at the pyruvate dehydrogenase step, the ATP/ADP ratio and the levels of CoAsAc, oxaloacetate and isocitrate in the Krebs cycle.
D000244:Adenosine Diphosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D002950:Citrate (si)-Synthase / Q000378:metabolism; D002952:Citric Acid Cycle; D004734:Energy Metabolism; D005227:Fatty Acids / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D006019:Glycolysis; D007521:Isocitrate Dehydrogenase / Q000378:metabolism; D007700:Kinetics; D008433:Mathematics; D008954:Models, Biological; D009132:Muscles / Q000378:metabolism*; D010732:Phosphofructokinase-1 / Q000378:metabolism; D011768:Pyruvate Dehydrogenase Complex / Q000378:metabolism
D005227:Fatty Acids; D011768:Pyruvate Dehydrogenase Complex; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D007521:Isocitrate Dehydrogenase; D002950:Citrate (si)-Synthase; D010732:Phosphofructokinase-1; D005947:Glucose
Mekhanizmy reguliatsii myshecgnogo energeticheskogo obmena pri okislenii gliukozy i zhirnykh kislot. Matematicheskaia model'.