The concept of the “Perisinusoidal Functional Unit” of the liver — importance to pathological processes

Summary Non-hepatocytes account for 30 per cent of cells in the liver, with sinusoid-coating endothelial and Kupffer cells being the most common types. In addition, there are some scattered pit cells in the wall. Ito cells (perisinusoidal cells, lipocytes) are located in the Disse space. In this paper a review is given of structural and functional changes of cells in response to pathological conditions with reference to the importance of such changes due to diseases of the liver and the organism in large. Cooperation and interaction among non-hepatocytes, the vascular pole of hepatocytes, and Disse space as the site of reaction are summarised under the concept of the “Perisinusoidal Functional Unit”, and the concept is explained in greater detail by examples (lipoprotein catabolism, processes of phagocytosis, vitamin A storage, virus infections, accumulation of pathological substances, fibrosis, and capillarisation).