Determination of tissue alpha-tocopherol in senescence-accelerated mice byhigh-performance liquid chromatography with fluorimetric detection

alpha-Tocopherol (alpha-Toc) plays an important role in various distinct ph ysiological functions. A convenient assay using high-performance liquid chr omatography with fluorimetric detection (the excitation and emission wavele ngth was 296 and 340 nm, respectively) was developed for the accurate deter mination of the alpha-Toe in biological samples. Methanol (1/7; v/v) was us ed to extract alpha-Toe in tissue samples by precipitating the proteins. Th e assay obtained a recovery rate between 97.3 and 104.2% by adding pure alp ha-Toe to mice liver homogenate. The R.S.D. for intra-day (n=7) and inter-d ay (n=6, three consecutive days) analysis was 0.7-2.8 and 0.5-3.7%, respect ively. The effect of age on the alpha-Toe levels in the liver, brain and he art homogenates of senescence-accelerated mice (SAM) was also studied. The alpha-Toe levels in the tissue homogenates increased gradually with age for both male and female mice, while the female had higher or-Toe levels than the males of the same age. (C) 2000 Elsevier Science B.V. All rights reserv ed.