Age-related changes in lipid peroxidation products in rat adrenal gland

Chloroform-methanol extracts from rat adrenals at five different ages (2, 6, 12, 18 and 24 months), were studied by fluorescence. After obtaining excitation and emission spectra, fluorescence intensity was measured at 365 nm excitation and 455 emission for all time points of aging. An additional study of lipid peroxidation employing a thiobarbituric acid reaction was made. Fluorescence intensity increased during aging from 16.39 x 10(3) arbitrary units of fluorescence per gram of tissue at 2 months, to 34.33 x 10(3) units at 24 months. Thiobarbituric acid reaction products expressed in nmol of malondialdehyde per gram of adrenal increased from 172.97 at 2 months to 640.83 at 24 months. One way analysis of variance revealed a statistically significant difference (p<0.05 and p<0.01 respectively). The results show an age-related steady increase in lipid peroxidation products in rat adrenals and suggest their accumulation in lipofuscin granules.