On the stability of key enzymes of energy metabolism in muscle biopsies.
Enzymes of energy metabolism were tested for stability depending on different storage conditions (-20, -80 degrees C). To avoid problems due to the different fiber type composition of human muscle, we selected two muscles from rabbit. The m. psoas consists almost exclusively of type 2B fibers, and the m. soleus consists almost exclusively of type 1 fibers. Enzyme activities were measured from small aliquots of these muscles at various time points up to 1 year after sacrificing the animal. Enzymes from anaerobic metabolism were stable for more than 1 year, independent of whether the muscle was stored at -20 or -80 degrees C. Oxidative enzymes, such as succinate dehydrogenase, citrate synthetase, or cytochrome c oxidase (COX) decrease in activity at -20 degrees C and, to a lesser degree, at -80 degrees C. In addition, mitochondria were isolated from freshly taken muscle and stored at -80 degrees C. Oxidative enzymes were surprisingly stable for more than 1 year, with the exception of COX which decreased by 60% of its original activity in mitochondria from m. soleus.
Pache
T
T
Department of Neurology, University of Würzburg, FRG.
Reichmann
H
H
D015094:3-Hydroxyacyl CoA Dehydrogenases / Q000378:metabolism; D000818:Animals; D001706:Biopsy; D002950:Citrate (si)-Synthase / Q000378:metabolism; D003576:Electron Transport Complex IV / Q000378:metabolism; D004734:Energy Metabolism; D004795:Enzyme Stability; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008931:Mitochondria, Muscle / Q000201:enzymology*; D009132:Muscles / Q000166:cytology / Q000201:enzymology* / Q000473:pathology; D009245:NADH Dehydrogenase / Q000378:metabolism; D006005:Phosphorylases / Q000378:metabolism; D011817:Rabbits; D013384:Succinate Cytochrome c Oxidoreductase / Q000378:metabolism; D013385:Succinate Dehydrogenase / Q000378:metabolism
D013384:Succinate Cytochrome c Oxidoreductase; D015094:3-Hydroxyacyl CoA Dehydrogenases; D007770:L-Lactate Dehydrogenase; D013385:Succinate Dehydrogenase; D009245:NADH Dehydrogenase; D003576:Electron Transport Complex IV; D002950:Citrate (si)-Synthase; D006005:Phosphorylases