Mitochondrial tissue specificity of substrates utilization in rat cardiac and skeletal muscles
| العنوان: | Mitochondrial tissue specificity of substrates utilization in rat cardiac and skeletal muscles |
|---|---|
| المؤلفون: | Ruddy Richard, Benoit Banga N'guessan, Elodie Ponsot, Bertrand Mettauer, Renée Ventura-Clapier, Joffrey Zoll, Florence Ribera, Eliane Lampert, Vladimir Veksler |
| المصدر: | Journal of Cellular Physiology. 203:479-486 |
| بيانات النشر: | Wiley, 2005. |
| سنة النشر: | 2005 |
| مصطلحات موضوعية: | Male, medicine.medical_specialty, Physiology, Cell Respiration, Clinical Biochemistry, Malates, Glutamic Acid, Oxidative phosphorylation, Mitochondrion, Biology, Oxidative Phosphorylation, Carnitine, Internal medicine, Pyruvic Acid, medicine, Animals, Glycolysis, Lactic Acid, Rats, Wistar, Muscle, Skeletal, Myocardium, Fatty Acids, Glutamate receptor, Substrate (chemistry), Cell Biology, Metabolism, Mitochondria, Rats, Adenosine Diphosphate, Kinetics, Metabolic pathway, Cytosol, Endocrinology, Glycerophosphates, Energy Metabolism, Oxidation-Reduction |
| الوصف: | As energetic metabolism is crucial for muscles, they develop different adaptations to respond to fluctuating demand among muscle types. Whereas quantitative characteristics are known, no study described simultaneously quantitative and qualitative differences among muscle types in terms of substrates utilization patterns. This study thus defined the pattern of substrates preferential utilization by mitochondria from glycolytic gastrocnemius (GAS) and oxidative soleus (SOL) skeletal muscles and from heart left ventrical (LV) in rats. We measured in situ, ADP (2 mM)-stimulated, mitochondrial respiration rates from skinned fibers in presence of increasing concentrations of pyruvate (Pyr) + malate (Mal), palmitoyl-carnitine (Palm-C) + Mal, glutamate (Glut) + Mal, glycerol-3-phosphate (G3-P), lactate (Lact) + Mal. Because the fibers oxygen uptake (Vs) followed Michaelis-Menten kinetics in function of substrates level we determined the Vs and Km, representing maximal oxidative capacity and the mitochondrial sensibility for each substrate, respectively. Vs were in the order GAS < SOL < LV for Pyr, Glu, and Palm-C substrates, whereas in the order SOL = LV < GAS with G3-P. Moreover, the relative capacity to oxidize Palm-C is extremely higher in LV than in SOL. Vs was not stimulated by the Lact substrate. The Km was equal for Pyr among muscles, but much lower for G3-P in GAS and lower for Palm-C in LV. These results demonstrate qualitative mitochondrial tissue specificity for metabolic pathways. Mitochondria of glycolytic muscle fibers are well adapted to play a central role for maintaining a satisfactory cytosolic redox state in these fibers, whereas mitochondria of LV developed important capacities to use fatty acids. |
| تدمد: | 1097-4652 0021-9541 |
| DOI: | 10.1002/jcp.20245 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a01feb8c1a2f2421b983a1605e82ecc6 https://doi.org/10.1002/jcp.20245 |
| Rights: | CLOSED |
| رقم الانضمام: | edsair.doi.dedup.....a01feb8c1a2f2421b983a1605e82ecc6 |
| قاعدة البيانات: | OpenAIRE |
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