Influence of hypothermia on chicken erythrocyte lipid peroxidation in vivo

The concentration changes of reactive products of thiobarbituric acid (TBARS) in blood plasma and hemolysate of erythrocytes and concentration changes of reduced glutathione (GSH) in whole blood were studied as well as the activities of lactate dehydrogenase (LDH) and aspartate-2-oxoglutarate transferase (AST) of blood plasma and erythrocytes in 8-week-old chickens exposed to hypothermia provided by cooling from normal colonic temperature of 41 degrees C to the temperature of 36 degrees C. During hypothermia lipid peroxidation in blood plasma, expressed as TEARS concentration, was significantly reduced (P < 0.01). At the same time the activities of LDH in chicken erythrocytes were significantly reduced (P < 0.05), while AST activities remained unchanged. Significant increase (P < 0.01) of AST activity was noticed only in blood plasma. According to the presented results one may conclude that this rise of AST activity in blood plasma was due to some other sources. In posthypothermia a significant increase in the plasma TEARS concentration (P < 0.05) was accompanied by a significant decrease of GSH concentration (P < 0.01) indicating the role of GSH as a scavenger and quencher of lipid peroxidation. It is proposed that lipid peroxidation is produced as the result of induced oxidative stress by hypothermia.