FATTY-ACID PROFILES AND NON ENZYMATIC LIPID-PEROXIDATION OF MICROSOMES AND MITOCHONDRIA FROM BOVINE LIVER, KIDNEY, LUNG AND HEART

The light emission = chemiluminescence and fatty acid composition, two markers of lipid peroxidation process, was evaluated in bovine liver, kidney, lung and heart microsomes and mitochondria incubated in the p resence of ascorbate-Fe2+ at 37 degrees C. Microsomal and mitochondria l fractions obtained from lung, kidney and heart were more resistant t o lipid peroxidation than those isolated from the liver. The ascorbate -Fe2+ seemed to be totally ineffective in stimulating peroxidation of bovine lung, heart and kidney microsomes or mitochondria. Whereas bovi ne liver microsomes or mitochondria displayed the highest values of ch emiluminescence when incubated in the presence of ascorbate-Fe2+. The peroxidizability index a parameter that indicate the maximal rate of o xidation of specific fatty acids showed statistically significant diff erences in mitochondria isolated from lung heart and kidney and micros omes isolated from lung. The fatty acid profile of the subcellular fra ctions obtained from those tissues do not appear to be responsible for their different susceptibility to free radical degradation. Other fac tor/s may be responsible for the protection to lipid peroxidation obse rved in microsomal or mitochondrial fractions obtained from bovine lun g, heart and kidney. KEYWORDS: Bovine, chemiluminescence, lipid peroxi dation, microsomes, mitochondria.