INFLUENCE OF PRESERVATION SOLUTIONS ON LIPID PEROXIDATION AND MITOCHONDRIAL RESPIRATION IN RAT KIDNEYS

Abstract
The role of hypothermic storage of rat kidneys on lipid peroxidation compared to its effect on mitochondrial respiratory parameters has been investigated. Rat kidneys were flushed with cold solutions of isotonic sodium chloride; Euro-Collins'; preservation solution containing histidine buffer, tryptophane, and α-ketoglutarate (HTK); or hypertonic citrate and then stored for 20 hr at 4°C. After storage, the endogenous contents of malondialdehyde as well as the chemically (by Fe2+/ascorbic acid) and enzymatically (by Fe3+/ADP/NADPH) induced generation of malondialdehyde were measured in cortical homogenates and partly in mitochondria and microsomes by the thiobarbituric-acid reaction. Compared to the values measured in fresh, unstored kidneys, the levels of malondialdehyde were significantly higher in kidneys preserved in solutions of isotonic sodium chloride or HTK. This stimulating effect of the HTK solution on the generation of lipid peroxidation products could also be established when homogenate was incubated with this solution. Euro-Collins' and hypertonic citrate solution did not change the endogenous contents of malondialdehyde in kidneys during hypothermic storage. Both the chemically and enzymatically induced lipid peroxidation increased after hypothermic storage of kidneys in all solutions investigated. No direct relationship between the contents of malondialdehyde and respiratory mitochondrial parameters was detectable. The results demonstrate that the extent of lipid peroxidation does not correlate with preservation effectiveness.