title: Isozyme selective induction of mouse pulmonary superoxide dismutase by the exposure to mercury vapor.
abstract: Alterations in lung superoxide dismutase (SOD) isozymes after exposure of mice to mercury vapor were examined. Inhalation of mercury vapor (10 mg/m(3)) for 1 h by mice resulted in a higher accumulation of mercury in the kidney and lung compared to other organs, at 1 h after exposure. Under these conditions marked enhancement of protein content in bronchoalveolar fluid (BALF), attributed to lung injury, was observed. Exposure to mercury vapor caused a significant increase in the pulmonary Cu,Zn-SOD activity (1.32-fold at 48 h) whereas Mn-SOD activity was suppressed to 82% of the control level, suggesting different sensitivity to the metal inhalation. The selective induction of Cu,Zn-SOD protein (1.79-fold at 48 h) was confirmed by immunoblot analysis with polyclonal antibodies against these isozymes. These observations suggest that the selective induction of Cu,Zn-SOD at the translational level appears to occur as an initial defense against mercury-promoted oxidative stress.
authors.affiliation: Department of Environmental Medicine, University of Tsukuba, Tsukuba, Ibaraki 305, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Shimojo
authors.forename: Y
authors.initials: Y
authors.lastname: Kumagai
authors.forename: S
authors.initials: S
authors.lastname: Homma-Takeda
authors.forename: M
authors.initials: M
authors.lastname: Shinyashiki
authors.forename: N
authors.initials: N
authors.lastname: Takasawa
authors.forename: K
authors.initials: K
authors.lastname: Kushida