Alcohol, aldehydes and lipid peroxidation: current notions.

The relations between membrane damage, lipid peroxidation and the effects of alcohol have attracted longstanding interest. In vitro studies showed that parameters of lipid peroxidation were positive. However, in vivo studies did not always provide clearcut conclusions. Our interest and that of a number of other groups, therefore, has centered on the intact organ and intact animal, using noninvasive indicators of lipid peroxidation such as ethane or pentane release and low-level chemiluminescence. The studies were mainly carried out with the isolated perfused rat liver, and there is substantial evidence for aldehydes being crucial in promoting lipid peroxidation. The range of aldehydes was extended from acetaldehyde to longer-chain aldehydes; in particular, aldehydes which themselves can originate from polyunsaturated fatty acid breakdown, e.g. 4-hydroxynonenal and congeners, were studied and were found to be potent in supporting lipid peroxidation.