Effects of Sulfur Dioxide Inhalation on Bronchoalveolar Lavage Fluid and Membrane Fluidity of Alveolar Macrophage in Rats

Abstract

Sulfur dioxide (SO2) is a ubiquitous air pollutant which causes kinds of damage to human and other organisms. However, the effects and mechanisms on the plasma membrane when cells and tissues were exposed to SO2were still unknown. The results herein showed a gradual reduction in body weight and dry lung weight for rats exposed to SO2. The wet lung weights were increased. The changes indicated SO2 inhalation caused pulmonary tissue permeability edema.Subscript textThe pulmonary permeability was increaseSubscript textSubscript textSubscript textd by the determination of protein contents in BALs and pulmonary permeability index (PPI). The intracellular proteins were penetrated into extracellular matrix. The total leukocytes in BALs of rats in each group exposed to SO2were significantly increased, and the granulocytes were also increased significantly. However, the lymphocytes in BALs of rats exposed SO2were to some extent different to the control groups. The activities of acid phosphatase (ACP), alkaline phosphatase (AKP) and lactic dehydrogenase (LDH) in BALs were increased to some extent. The results showed that the functions of plasma membrane were damaged with the damage of membrane structure, parts of the membrane bound enzymes and intracellular enzymes were released into BALs. The membrane fluidity in AM cells were significantly decreased by the determination of steady-state fluorescent polarization degree (P) and fluorescence microviscosity (η) of the AM.