Malondialdehyde is a biochemical marker of peroxidative damage in the isolated reperfused rat heart

Concentration of MDA in isolated control, ischemic, and reperfused rat hearts was determined by using a new sensitive and reproducible HPLC method on the perchloric acid extract of the freeze-clamped tissues. By means of this HPLC assay for the direct measurements of MDA, concentrations of adenine nucleotide derivatives were also obtained in the same chromatographic run. Under the present experimental conditions, no detectable amount of MDA could be observed in control hearts while ischemic hearts showed 0.009moles/g d. w. of MDA (s. d. = 0.001), this value representing the sensitivity limit of the method employed. On the contrary, reperfused hearts showed 0.118moles/g d.w. of MDA (s.d. = 0.036), thereby indicating that this compound originates from an oxygen free radical-mediated breakdown of phospholipids and demonstrating the existence of quantifiable molecular damage occurring upon reperfusion. On the whole, our data demonstrate that MDA, if properly assayed, is a reliable index of peroxidative injury to biological systems. (Mol Cell Biochem116: 193–196, 1992)Abbreviations Ado Adenosine - d.w. dry weight - HPLC High-Performance Liquid Chromatography - Hyp Hypoxanthine - Ino Inosine - MDA Malondialdehyde - Xan Xanthine