RESUMO
Copaiba oleoresin is widely used in folk medicine as an antiinflammatory, healing and antiseptic agent. Wistar rats received Copaifera duckei oleoresin (CDO) or saline solution (SS) from 7 days before surgery until killing. Partial hepatectomy (PH) or sham-operation was performed. Hepatocellular proliferation and liver mitochondrial respiration were evaluated 24 h after the procedure. The proliferating cell nuclear antigen labelling index was significantly lower in CDO-treated plus PH rats than in SS-treated plus PH rats, suggesting that CDO inhibited cell proliferation. The state 3 and state 4 respiration rates were greater for CDO-treated groups, and the stimulation of state 4 respiration was more expressive. These data resulted in a significant decrease in the respiratory control ratio observed for CDO-treated groups, demonstrating the ability of CDO to uncouple oxidative phosphorylation in mitochondria, a fact that may be one explanation for the inhibition of hepatocellular proliferation observed in the CDO-treated plus PH group.