[Pathogenesis of atherosclerosis: an update on the three main theories].

The causes and mechanisms of atherosclerosis remain incompletely understood. Almost all the present investigations are still connected with one of the main three historical theories of atherosclerosis: 1) the incrustation theory, as developed by von Rokitansky, has now led to the many studies on the roles of thrombosis and platelets; 2) the irritation theory, as opposed to the preceding one by Virchow and his school, is reviving through the rediscovery that leukocytes are present in the plaques, and that atherosclerosis (Virchow's endarteritis chronica deformans sive nodosa) has the features of a chronic inflammatory reaction; 3) the lipid infiltration theory, as initiated by the experiments of Anitschkov and Chalatov in rabbits fed a cholesterol enriched diet, motivates the huge mass of studies devoted to plasma lipids and their cellular metabolism. This article provides a brief update on each of these three complementary approaches of atherosclerosis.