Localization of Cu/Zn-SOD and Mn-SOD in the rat cochlea.

Distributions of the copper/zinc-superoxide dismutase (Cu/Zn-SOD) and the manganese superoxide dismutase (Mn-SOD) in the rat cochlea were studied by immunohistochemistry with specific polyclonal antibodies to Mn-SOD and Cu/Zn-SOD. Coexpression of Mn-SOD and Cu/Zn-SOD was observed in the cochlear tissues with differing immunoactivity intensities. The presence of Cu/Zn- and Mn-SOD implies the existence of a defense system against free oxygen radical (FOR) injury in cochlear tissues.