Lipid peroxidation in the heart of adult and old rats during immobilization stress

This study was designed to assay the lipid peroxidation (LPO) in the heart from adult (10-12 months) and old (22-25 months) Wistar male rats during im mobilization stress. A value of LPO was estimated according to the concentr ation of conjugate dienes, TEA-positive substances and fluorescent products such as Schiff base. Investigations have shown that immobilization of rats was accompanied by increase in the concentration of all studied LPO interm ediates in myocardium from both the age groups. Accumulation of these metab olites in old rat hearts was considerably higher than in adult ones. Dimeth yl sulfoxide injection has limited stress-induced stimulation of LPO. Chang es revealed in LPO-stimulation have different consequences in pathogenesis of stress dependent injury in myocardium from adult and old rats. Utilizati on of LPO metabolites in old rats takes place mainly with formation of Schi ff base. Accumulation of these products in myocardium is accompanied by mod ification of intracellular macromolecules and thus promotes the enhancement of stress-induced injury of myocardial cells. In adult rats during stress, the utilization of malonic dialdehyde and substances homologous to it is n ot accompanied by Schiff base accumulation in myocardium. It may be importa nt for the restriction of stress-induced injury of myocardial cells. (C) 20 01 Elsevier Science Inc. All rights reserved.