The Focal Induction of Reactive Oxygen Species in Rats as a Trigger of Aortic Valve Degeneration.

Background: Degenerative aortic valve disease (DAVD) is a multifactorial process. We developed an animal model to analyze the isolated, local effect of reactive oxygen species (ROS) on its pathophysiology.

Methods: We utilized a photodynamic reaction (PDR) as a source of ROS in the aortic valve by aiming a laser at the aortic valve for 60 min after the administration of a photosensitizer 24 h prior. ROS, laser, and sham groups ( = 7 each) for every observation period (t = 0; t = 8 d; t = 84 d; t = 168 d) were established. The amount of ROS generation; morphological changes; inflammatory, immune, and apoptotic reactions; and hemodynamic changes in the aortic valves were assessed using appropriate histological, immunohistological, immunohistochemical, and echocardiographic methods.

Results: The ROS group displayed an increased amount of ROS ( < 0.01) and increased inflammatory activation of the endothelium ( < 0.05) at t = 0. In the ROS group, aortic valves were calcified ( < 0.05) and the transvalvular gradient was increased ( < 0.01) at t = 168 d.

Conclusion: The small animal model employed here may serve as a platform for analyzing ROS's isolated role in the DAVD context.