Comparative analysis of superoxide dismutase activity between acute pharmacological models and a transgenic mouse model of Huntington's disease

We examined the activity of striatal superoxide dismutase (SOD) in two acut e pharmacological models of Huntington's disease (HD), and compared it with SOD activity in the striata of mice transgenic for the HD mutation. Total SOD, and Cu/ZnSOD activities increased in young transgenic mice, but decrea sed in older (35 week) mice. We consider that the increased enzyme. activit y represents a compensatory mechanism to protect cells from free radical-in duced damage, but the system becomes insufficient in older animals. Major d ecreases in SOD activity were also observed both after quinolinic acid and 3-nitropropionic acid intrastriatal injections. The present results indicat e that in both types of HD models striatal oxidative damage occurs, and tha t it is associated with alterations in the cellular antioxidant system.