Toxicology and applied pharmacology
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Toxicol. Appl. Pharmacol. · Mar 1986
Erythrocyte superoxide dismutase activity and other parameters of copper status in rats ingesting lead acetate.
The effects of lead ingestion on parameters indicative of copper status, and particularly on the activity of the copper-dependent metalloenzyme superoxide dismutase (SOD) in erythrocytes, were investigated in weanling and neonatal rats. In a series of experiments, Sprague-Dawley or Long-Evans rats were fed a nutritionally adequate purified diet (AIN-'76). Lead acetate was given orally in the drinking water (0, 100, 250, or 500 ppm Pb) to groups of 23 to 26-day-old rats for 5 weeks or intragastrically (0, 5, 11, 22, or 45 mg Pb/kg body wt/day) to pups from postnatal Days 2 through 20. ⋯ Despite high blood lead concentrations (1-3 micrograms/ml), SOD activity was not decreased in the neonatal rat. In addition, lead had no direct effect in vitro on the activity of bovine blood superoxide dismutase. On the basis of both the in vitro and in vivo studies, it appears likely that the observed decrease in SOD in young rats is caused indirectly by a lead-induced copper deficiency rather than by a direct inhibitory effect of lead.