Pleurodesis induction in rats by Copaiba (Copaifera multijuga Hayne) oil

This study aims to assess and compare copaiba oleoresin of Copaifera multijuga and 0.5% silver nitrate for the induction of pleurodesis in an experimental model. Ninety-six male Wistar rats were divided into three groups: control (0.9% saline solution), copaiba (copaiba oil), and silver nitrate (0.5% silver nitrate). The substances were injected into the right pleural cavity and the alterations were observed macroscopically and microscopically at 24, 48, 72, and 504 h. The value of macroscopic alterations grade and acute inflammatory reaction grade means was higher in the 24 h copaiba group in relation to silver nitrate. Fibrosis and neovascularization means in the visceral pleura were higher in 504 h copaiba group in relation to the silver nitrate group. The grade of the alveolar edema mean was higher in the silver nitrate group in relation to the copaiba group, in which this alteration was not observed. The presence of bronchopneumonia was higher in the 24 h silver nitrate group (n = 4) in relation to the copaiba group (n = 0). In conclusion, both groups promoted pleurodesis, with better results in copaiba group and the silver nitrate group presented greater aggression to the pulmonary parenchyma.