[Cellular and extracellular changes in the regression of experimentally-induced arteriosclerosis and their relevance for the regression of arteriosclerosis in humans].

In a survey the essential cellular and extracellular structural changes in the regression of experimentally induced changes of the arteries and their functional importance are discussed. All animal experiments show that early changes such as lipidosis and proliferation of the intima are totally reversible and more advanced atheroma-like stages of the experimental atherosclerosis are conditionally and incompletely reversible. The endothelial cell layer, the muscle cells of the plaques and the macrophages of the plaques with different time sequence and importance for the process of regression participate in the retrogression of induced plaques. With the removal of the atherogenic factor(s), in the animal experiment mainly hypercholesterolaemia and/or mechanical lesion of the vascular wall, the repair of the endothelial cell layer, the destruction and revival of the macrophages of the plaques, the elimination of intra- and extracellularly accumulated cholesterol esters in muscle cells and macrophages, the normalisation of the cell division rate and the fibrosynthesis of plaque muscle cells. On the many respects unclarified metabolic ways plaque muscle cells and macrophages participate in the absorption of extracellular matrix. The animal experimental, fairly optimistic results must not necessarily be valid also for man. In advanced stages of the atheroma of the aged man the basic conditions of reversibility, which are guaranteed in the animal experiment, are not given.