Abstract:The aortic wall comprises three layers: the intima, the media, and the adventitia. Among them, the media layer is the most complex in tissue structure, carrying the most functions, and is also the primary cause and site of aortic diseases. The main structural components of the aortic media layer are the extracellular matrix (ECM), composed of elastic fibers (EF) and collagen fibers (CF). EF and CF contribute to the local microenvironment of the arterial wall and play a crucial role in maintaining the normal morphology and mechanical characteristics of the aortic wall. EF is associated with the good compliance of the vessel wall, while CF is associated with the ultimate strength of the wall. The interweaving of these two components allows the aortic wall to possess both elasticity and toughness. In this article, the author provides an overview of the composition of the fibrous structure in the aortic wall and the synthesis, expression, and functions of each component.