Cytochrome c oxidase and purine nucleotides in skeletal muscle in tumour-bearing exercising rats.
We have previously shown that spontaneous physical exercise can delay the onset of experimental anorexia and cachexia and retard tumour growth and we now report the effects on the energy metabolism in skeletal muscle. Exercising tumour-bearing animals (TBE) had an increased maximal capacity for oxygen uptake expressed as Vmax of the cytochrome c oxidase compared with their tumour-bearing sedentary controls (TBS) [mean (S.E.) 289.9 (30.7) vs. 141.6 (11.0); P less than 0.05] but an unchanged Km value. The TBS animals had a depressed Vmax as compared with non-tumour-bearing sedentary controls (CS) [141.6 (11.0) vs. 210.1 (15.1); P less than 0.05]. Most of the purine nucleotides in the 'glycolytic' anterior tibial muscle were significantly altered in the TBE animals compared with the TBS animals, but in the mainly 'oxidative' soleus muscle only the level of inosine monophosphate (IMP) was changed. The results indicate that physical exercise can normalise the oxidative capacity and improve the energy state in skeletal muscle in the tumour-bearing host.
Daneryd
P
P
Wallenberg Laboratory, Department of Surgery, University of Göteborg, Sahlgrenska Hospital, Sweden.
Karlberg
I
I
Scherstén
T
T
Soussi
B
B
D000818:Animals; D001835:Body Weight / Q000502:physiology; D004435:Eating / Q000502:physiology; D003576:Electron Transport Complex IV / Q000378:metabolism*; D004734:Energy Metabolism / Q000502:physiology; D005260:Female; D007700:Kinetics; D008954:Models, Biological; D009132:Muscles / Q000201:enzymology*; D009368:Neoplasm Transplantation; D009374:Neoplasms, Experimental / Q000201:enzymology* / Q000503:physiopathology; D010100:Oxygen / Q000378:metabolism; D010805:Physical Conditioning, Animal; D011685:Purine Nucleotides / Q000378:metabolism*; D051381:Rats; D011920:Rats, Inbred WF
D011685:Purine Nucleotides; D003576:Electron Transport Complex IV; D010100:Oxygen