Cell shrinkage

Woollhead AM, Baines DL (2006) Forskolin-induced cell shrinkage and apical translocation of functional enhanced green fluorescent protein-human alphaENaC in H441 lung epithelial cell monolayers. J Biol Chem 281 (8) 5158—5168... 

Figure 20.34 A simple representation of the processes of necrosis and apoptosis leading to the death of cells. Necrosis is initiated by a decrease In the ATP/ADP concentration ratio, which slows ion pumps, which leads to cation imbalance (e.g. ca ion entry into the cytosol) and hence intracellular damage, entry of water and lysis which can lead to local inflammation. Apoptosis is initiated by specific extracellular or intracellular factors, which lead to cell shrinkage and disruption into apoptotic bodies which are removed by phagocytes.

Most studies were performed with hyperosmolar solutions. Hypertonic disruption is under clinical evaluation for enhanced delivery of small molecular weight cytostatic agents to brain tumours. Technically, the procedure is performed as a high-flow short-term infusion of 25% mannitol or arabinose under general anaesthesia. The underlying mechanism is a sequelae of endothehal cell shrinkage, disruption of tight junctions and vasodilatation by osmotic shift [72]. 

Nobel CS, Aronson JK, van den Dobbelsteen DJ, Slater AF. Inhibition of Na+/K(+)-ATPase may be one mechanism contributing to potassium efflux and cell shrinkage in CD95-induced apoptosis. Apoptosis 2000 5(2) 153-63. 

Cells in suspension must be frozen rapidly in order to encourage the formation of small ice crystals rather than the large ones which would rupture membranes. The same principle holds for cells attached to surfaces but there is a complication. When cells are frozen in suspension, it is usual to choose conditions which promote some degree of cell shrinkage to prevent rupture of the cell membrane (Fig. 18). However, shrinkage of a cell adhered to a surface creates... 

Liver cell swelling not only inhibits proteolysis, but also stimulates protein synthesis. In sharp contrast, cell shrinkage stimulates proteolysis but inhibits protein synthesis (Stoll et al., 1992). That cell hydration affects both protein degradation and synthesis in opposite directions is a finding that has a direct bearing on the problem of protein-catabolic states in disease (see p. 204). 

It is controversial whether apoptotic cardiomyocytes in human MI exhibit characteristic morphological features such as cell shrinkage, condensation of chromatin, and fragmentation into apoptotic bodies [18]. It is also unknown how an apoptotic cardiomyocyte is released from the tight connection... 

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