TABLE 1.

Age-associated changes in antioxidant levels and oxidative damage in the heart^a

	Young	Old
Ascorbate (nmol/mg protein ± SE)	3.08 ± 1.10	1.40 ± 0.87*
α-Tocopherol (nmol/mg protein ± SE)	0.97 ± 0.29	1.16 ± 0.62
C + Sc8-oxo-dG (8-oxo-dG/1 × 105 dG bases)	2.01 ± 0.25	4.00 ± 0.40 #
C + ScF2-isoprostanes (ng/g wet tissue)	3.47 ± 0.02	3.74 ± 0.41

^aAscorbate and α-tocopherol levels in the freshly isolated heart from young and old rats were measured using electrochemical detection following separation by HPLC. The results show a significant decline in the ascorbate levels. In contrast, lipid-soluble antioxidant α-tocopherol did not change with age. As a measure of oxidative damage to DNA and lipids, 8-oxo-dG and F₂-isoprostanes were measured using coulometric electrochemical detection and GC-MS. The results show a twofold increase in steady-state levels of 8-oxo-dG. However, there was no change in steady-state levels of ± SE; F₂-isoprotanes with age. The results are expressed as mean statistical analysis was done by using the Student’s t test.

^*P = 0.02;

^#P = 0.002.