[Effect of freezing-thawing rates on the functional state and ionic permeability of rat liver mitochondria].
The effects of various rats of freezing-thawing reactions on the functional state and ionic permeability of rat liver mitochondria were studied. The degree of mitochondrial damage during the freezing -- thawing process depended on the rate of thawing rather than on that of freezing. The mitochondria which were slowly or rapidly frozen down to --196 degrees and subsequently slowly thawed revealed a higher membrane permeability for K+ Na+ and H+ and a more than 2-fold increase of the ATPase activity and the maximal rate of NADH oxidation via the antimycin-insensitive pathway in the presence of cytochrome c. This was concomitant with a complete inhibition of the ATP-synthetase activity and a marked inhibition of the respiratory chain function due to the efflux of cytochrome c from the inner mitochondrial membrane. After freezing and rapid thawing the functional activity of mitochondria changed insignificantly. A comparison of different cryoeffects demonstrated that the minimal damaging effects were exerted by rapid freezing -- rapid thawing, when the mitochondria partly restored their ability for oxidative phosphorylation.
D025181:ATP Synthetase Complexes; D000244:Adenosine Diphosphate / Q000378:metabolism; D000251:Adenosine Triphosphatases / Q000378:metabolism; D000818:Animals; D003574:Cytochrome c Group / Q000378:metabolism; D005615:Freezing; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008297:Male; D008930:Mitochondria, Liver / Q000378:metabolism*; D009097:Multienzyme Complexes / Q000378:metabolism; D009243:NAD / Q000378:metabolism; D010084:Oxidation-Reduction; D010539:Permeability; D010770:Phosphotransferases / Q000378:metabolism; D011188:Potassium / Q000378:metabolism; D051381:Rats; D012964:Sodium / Q000378:metabolism
D003574:Cytochrome c Group; D009097:Multienzyme Complexes; D009243:NAD; D000244:Adenosine Diphosphate; D012964:Sodium; D010770:Phosphotransferases; D025181:ATP Synthetase Complexes; D000251:Adenosine Triphosphatases; D011188:Potassium
Vliianie skorosti zamorazhivaniia i otogreva na funktsional'noe sostoianie i ionnuiu pronitsaemost' mitokhondriĭ pecheni krys.