Role of the altered transmural permeability in the pathomechanism of arteriosclerosis. History of arteriosclerosis theories. Role of the altered permeability in experimental arteriosclerosis models.

After presenting an overview on classification and history of arteriosclerosis theories, the physiological factors involved in the transmural permeability of the arteries are discussed in detail. The development and characteristic features of the altered transmural permeability were studied in various experimental models such as in rat's hypercholesterolemia, local aortic hypoxia, lymphedema of the vascular wall and in hypertension. Results appear to show that alterations in permeability invariably developed in all of the pathological conditions examined, they were transient in nature and preceded the onset of intimal proliferation(s). The disturbance of transmural permeability might be the common pathologic clue which initiates uniform vascular responses to injuries produced by a variety of noxious stimuli. The possible role of the altered transmural permeability in the induction of smooth muscle cell proliferation is also discussed and evidence is provided that after withdrawal of stimulus for vascular injury intimal proliferation will not develop despite the manifest disorders in permeability.