Effects of Malonaldehyde Contents in Eschar Extract on Mitochondric Respiratory Function and Energization of the Inner Membrane

Extract of the eschar tissue taken from the rat which had been given full-thickness burn of20% TBSA was found to be inhibitory to the respiratory function of the mitochondria and theenergization of the inner membrane. The inhibition was also demonstrated by the 1: 2 and 1: 4and 1: 8 dilutions of the eschar extract. The extract of normal skin only showed weak inhibitory cf-fect. The 1: 4 dilution of normal skin had no (?) on mitochondrial functions. There is a widegap between the malonaldehyde (MDA) contents of these two kinds of extracts. An apparent posi-tive correlation was found between MDA content and degree of inhibition. However, on close ex-amination, it was found that the MDA content is not the direct cause of the decrease of therespiratory control ratio (RCR). The increase of MDA content is probably related to the destruc-tion of the lipid bilayer of the mitochondria. Data from the energization experiment show that theenergization process is compromised when the destruction of the membrane has proceeded to a cer-tain degrce. The inhibition of mitochondrial respiratory function becomes evident when encrgizationfunction is still normal. Therefore at least two mechanisms are operating in the inhibition process.Further work is needed to elucidate the problem.