pubmed-article:44843 | pubmed:abstractText | Phosphorylation rates of canine heart mitochondria isolated after various periods of myocardial ischemia after cardioplegic arrest were correlated with the myocardial ATP-, lactate- and undissociated lactic acid content as well as with interstitial H+-concentration. The following correlation coefficients were found: ATP: 0.87, lactate: 0.93, interstitial H+: 0.73. The calculated undissociated lactic acid content and the mitochondrial phosphorylation rate during ischemia showed a correlation coefficient of r = 0.95. Swelling measurements of mitochondria, isolated immediately after cardioplegic arrest, demonstrated that an undissociated lactic acid- and an ATP-concentration of 70 microM and 28 microM respectively are necessary for a half maximal swelling reaction under anaerobic conditions. The results suggest that the accumulation of undissociated lactic acid during myocardial ischemia could play an important role for mitochondrial damage in vivo. | lld:pubmed |