PROTECTIVE EFFECT OF AMBROXOL AGAINST HEAT-INDUCED AND HYDROGEN-PEROXIDE-INDUCED DAMAGE TO LUNG LIPIDS IN MICE

We wanted to determine whether ambroxol, a drug which stimulates the r elease of surfactant by type II pneumocytes, can protect lung lipids f rom peroxidative damage in mice. Animals were injected intraperitoneal ly with ambroxol, 0.169 mmol.kg(-1) or 1 ml buffer once a day for thre e consecutive days. Lipid peroxidation was then induced in lung homoge nates either by means of heat, 50 degrees C, or H2O2, 10 mmol.l(-1). T he lung homogenates from ambroxol-treated animals revealed decreased l ipid peroxidation in response to both stimuli. The heat- and H2O2-indu ced generation of conjugated dienes (a first lipid peroxidation produc t) in ambroxol-treated lung homogenates was 3.7 and 3.1 fold lower tha n in the lungs from buffer-injected mice. Ambroxol, as an inhibitor of heat- and H2O2-induced lipid peroxidation, was equipotent to and stro nger than the two antioxidants, N-acetylcysteine and methionine, respe ctively. Ambroxol was not able to protect heart and liver lipids. Thes e results suggest that ambroxol can sufficiently enhance the antioxida nt defence in lung tissue and can act as a lung lipid antioxidant.