Electronic Thesis and Dissertation Repository


Master of Science


Physiology and Pharmacology


Dr. Ruud Veldhuizen

2nd Supervisor

Dr. Cory Yamashita

Joint Supervisor


Pulmonary surfactant is a lipoprotein mixture responsible for reducing surface tension of the lung. In this thesis, we investigate the impact of lung injury on surfactant composition and function, with a specific focus on cholesterol content. First, the impact of a high cholesterol diet on surfactant function was assessed in three models of lung injury. It was hypothesized that serum hypercholesterolemia would increase host susceptibility to surfactant functional impairments. Secondly, the impact of injurious ventilation on intracellular surfactant within the lung was investigated. It was hypothesized injurious ventilation would produce alterations to lamellar body surfactant. Overall, the data suggest that a high cholesterol diet contributes to altered surfactant function during lung injury. Additionally, injurious ventilation promoted functional impairments to intracellular surfactant prior to secretion into the airspaces. In conclusion, we provide evidence of diet induced alterations to surfactant function and novel insight into intra-alveolar alterations to surfactant during mechanical ventilation