Cell swelling

Some of the discomfort of warm environments, the perception of skin moisture, and the interactions of clothing fabrics with the skin may be due to the moisture itself. The skin s outer layer of dead squamous cells of the stratum corneum can readily absorb or lose water. With moisture addition, the cells swell and soften. With drying, they shrink and become hard. In this setting the skin s moisture may be better indicated or characterized by the relative humidity of the skin (RH i ) rather than skin wettedness,-" ... 

The disruption of C1C-2 in mice leads to male infertility, blindness, and leukodystrophy, and was attributed to defective extracellular ion homeostasis in narrow clefts. C1C-2 yields currents that slowly activate upon hyperpolarization. It is also activated by cell swelling and by extracellular acidification. Structural determinants that are essential for these types of activation were identified by mutagenesis. There is a report that C1C-2 might be mutated in human epilepsy, but this has not been confirmed in fiuther studies. 

Cells are normally kept at osmotic (water activity) equilibrium by the action of the Na-pump. Inhibition of the pump with the specific Na -K -ATPase inhibitor, ouabain, causes cell swelling as does inhibition of it by hypothermia. The intracellular environment contains a high concentration of K (100 to 120 mM, in most mammalian cells), lower concentrations of Na (about 10 to 30 mM), and high... 

Lactobionic acid lOOmM Impermeant, suppresses cell swelling, Ca and Fe chelator... 

Hydroxyethyl starch 5g%(50g/1) Impermeant colloid, suppresses cell swelling... 

Many of the morphological and biochemical changes that occur in cells that die by necrosis are very different from those that occur in apoptosis. During necrosis cells swell, mitochondria and endoplasmic reticulum lose their structure and become dysfunctional and the nuclear membrane becomes disrupted (Fig. 35-1). Necrotic death is independent of premitochondrial apoptotic proteins such as Bax, cytochrome c release and caspase activation. Necrosis is further distinguished from apoptosis by the fact that necrosis usually occurs as the result of a traumatic physical injury or stroke and cells die en masse, whereas apoptosis typically occurs in individual cells within a population of surviving neighbors. 

Necrosis is a dramatic and very rapid form of cell death in which essentially every compartment of the cell disintegrates. Necrosis is characterized by marked dysregulation of ion homeostasis resulting in cell swelling, dilation of mitochondria and the ER and the formation of vacuoles in the cytoplasm [33], Proteases play important roles in the degradation of cells during necrosis. In contrast to apoptosis, where caspases are the key death proteases, calpains and lysosomal proteases (cathepsins B and D, in particular) are major players in necrosis. Caspases may be activated in response to mitochondrial damage and... 

As the buffer used in these studies [86, 158] is hypotonic to rat peritoneal mast cells, incubations of greater than 10 min result in significant cell swelling, a large increase in membrane permeability, as judged by trypan blue staining, and eventually cell lysis. This raises some concern as to the location of the site... 

Light microscope (LM) studies showed that ECT caused distinct changes to the cellular structure of treated tumors. In the anodic area, the nuclei shrank and cytoplasmic structure disappeared.37 In the cathode area, the cells swelled and the interface among cells blurred. Repeatedly, one observes swelling in the cathode area (oedema) and dehydration around the anode — this key observation can only be explained in terms of electroosmotically driven water from anode to cathode, to be discussed in details in the Section on Mechanistic Studies. 

The steps of apoptosis are distinct from those of necrosis which is a nonprogramed form of cell death in response to injury, in which the cell swells and bursts, causing inflammation. Apoptosing cells form a tight sphere and their membranes undulate, resulting in bulges that form blebs. The nuclear membrane breaks, and endonucleases clip chromosomes where the DNA is exposed from protective proteins. This occurs at 180-base... 

Histological examination of the liver reveals extensive cen-trilobular necrosis with loss of characteristic architecture of the hepatic cords. TEM examination indicated that both hepatocytes and hepatic endothelial cells were destroyed. The only alterations noted prior to cell rupture were slight mitocondrial swelling and slight cell swelling. Damaged cells had extensive fragmentation and vesiculation of the membrane (34). 

Failure Marked impairment of energy homeostasis with volume contraction impaired mitochondrial reductive activity with decreased ATP concentration (e.g., MTT, Alamar blue) organelle and cell swelling and distortion, cell lysis with intracellular enzyme release (e.g., LDFf release)... 

The irradiation of the vein for 15 min caused smoothing of the folds and wrinkles on the endotheliocyte surface. The cell swelling influenced the intercellular space which became wider (Fig. 30.2b). 

In addition, electroporation should ideally be carried out in a hypoosmolar buffer, which induces cell swelling [19]. However, for sensitive cell types even limited incubation in such hypoosmolar buffers can lead to apoptosis, so these cells should preferentially be treated in isoosmolar buffer systems. 

Zhou, Y. Y., Yao, J. A., and Tsen, G. N. 1997. Role of tyrosine kinase activity in cardiac slow delayed rectifier channel modulation by cell swelling. Pfliigers Arch. 433 750-757. 

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