Superoxide dismutase activity in early stages of development in normal and dystrophic chickens.

Changes in superoxide dismutase activities in early stages of chronological development were investigated in normal and dystrophic chickens. Both cupro-zinc and manganese superoxide dismutase activities were significantly elevated in the dystrophic chickens studied as early as one week after hatching compared to those in the control. In control chickens, both cupro-zinc and manganese superoxide dismutase activities declined as they grew older. In dystrophic chickens, manganese superoxide dismutase activity declined gradually as they grew older as in the control. However, cupro-zinc superoxide dismutase activity increased until four weeks of age. The latter activity was still twice as high as that of the control at four months of age. Increased activities in superoxide dismutases in early stages of the development suggest presence of increased turnover of active oxygen species from the early stage of the disease in this avian muscular dystrophy. And the distinct time course of cupro-zinc superoxide dismutase activity suggests involvement of active oxygen species in pathogenesis of this disorder.