Objective: To evaluate the protective effect of ambroxol on acute hydrochloric acid-induced lung injury in rats.
Methods: Thirty pathogen-free SD rats were randomly divided into 3 groups: Group A (n=10) served as control group, and received intracheal instillation of normal saline (NS, pH5.3, 1.2 ml/kg) with pre-treatment of intraperitoneal NS; Group B (n=10) received intracheal instillation of hydrochloric acid /NS (pH1.25, 1.2 ml/kg) with pre-treatment of intraperitoneal NS; and Group C received intracheal instillation of hydrochloric acid /NS (pH1.25, 1.2 ml/kg) with pre-treatment of intraperitoneal ambroxol (50 mg/kg/d, 3 days). Five hours after the instillation of the injury vehicle, the arterial gas was examined, the levels of superoxide dismutase (SOD), malondialdehyde (MDA) in the blood and homogenate of harvested lung were assayed respectively.
Results: PaO2 in Group B was significantly lower than that in Group A and C (P < 0.01), and pH and PaCO2 in the 3 groups had little difference (P > 0.05). MDA in the lungs of Group B increased obviously, and levels of SOD in the lung and blood decreased significantly in Group B (Group B vs Group A, P < 0.01). Levels of SOD of Group C in the lung and blood were markedly higher than those of Group B (P < 0.01), MDA of Group C was obviously lower than that of Group B (P < 0.01), and MDA of blood in the 3 groups had no significant difference (P > 0.05).
Conclusion: Ambroxol can inhibit lipid peroxidation and increase antioxidant activity, which may be one of the mechanisms in protecting lung tissue from hydrochloric acid-induced injury.