AGE-RELATED-CHANGES IN ANTIOXIDANT DEFENSE-MECHANISMS AND PEROXIDATION IN ISOLATED HEPATOCYTES FROM SPONTANEOUSLY HYPERTENSIVE AND NORMOTENSIVE RATS

The effects of age and hypertension on the antioxidant defence systems and the lipid peroxidation in rat isolated hepatocytes were studied. Four different age groups (1, 3, 6 and 12 months) were considered in s pontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WK Y) rats. Age-associated changes were observed on vitamin E status, glu tathione (GSH) level, MDA formation and glutathione peroxidase (GSH-Px ) activity in both strains. Maximal levels or activities of these para meters were found at 3 and 6 months, except for MDA which was low at 3 months. Then, a fall was observed at 12-month-old compared to 6-month values. In addition, GSH-Px activity was significantly lower in SHR t han in WKY rats, except at the age of one month. The decrease of this enzyme activity could induce an increased cellular generation of radic al species and lipid peroxidation, which might be link to hypertension .