Cell membrane alterations

Although the topic of anaesthesia is hugely complicated, it is clear that the physiological effect of the compounds depends on their entrapment in the blood. Once dissolved, the compounds pass to the brain where they promote their narcotic effects. It is now clear that the best anaesthetics dissolve in the lipids from which cell membranes are generally made. The anaesthetic probably alters the properties of the cell membranes, altering the rates at which neurotransmitters enter and leave the cell. 

Peridex Disrupts cell membranes Altered taste sensation O O... 

Mechanism of Action A fungistatic antifungal that inhibits the synthesis of ergos-terol, a vital component of fungal cell formation. Therapeutic Effect Damages the fungal cell membrane, altering its function. 

Chemicals produce adverse effects in the developing embryo and fetus by a variety of mechanisms (Bishop Kimmel, 1997). These may involve interactions of the exogenous agent with endogenous receptors, adduction of reactive intermediates to DNA or proteins, lipid peroxidation, enzyme inhibition, cell membrane alterations and others (US NRC, 2000). 

Palta, J. P., Jensen, K. G., Li, P. H. 1982. Cell membrane alterations following a slow freeze thaw cycle ion leakage, injury and recovery. In Plant Cold Hardiness and Freezing Stress. Vol 2. Li, P. H., Sakai, A. (eds.). Academic Press, New York, pp. 221-242. 

In contrast, conduction velocity is slow in muscle fibers at the SA and AV nodes. Unlike the majority of cardiac muscle cells, these pacemaker cells have an unstable resting potential ( — 60 mV) due to a cell membrane alteration that allows sodium ions to leak into the cell without a concurrent potassium ion efflux. This sodium leakage reduces the membrane potential allowing even more sodium ions to move into the cell. In addition to the inward sodium movement, there is also an inward calcium flow which causes the pacemaker cells to have a more positive resting potential. Finally, the cell produces an action potential at 40 mV. This phenomenon is called spontane-... 

Natamycin is an ophthalmic antifungal agent, which binds to fungal cell membrane, altering membrane permeability and depleting essential cellular constituents. A polyene mac-rolide antibiotic (instill 1 drop of 5% solution in conjunctival sac), natamycin is used in conjunctivitis, keratitis, and blepharitis caused by susceptible fungi. 

Cell Membrane Alterations (Surface Lipid Translocation)... 

Wengler and Wengler (1972) have shown that increased osmo-larity of the growth medium inhibits the initiation of protein synthesis in vivo. Nuss et at. (1975) have also selectively blocked initiation of host protein synthesis in RNA virus-infected cells. Saborio et al. (1974) found that cellular protein synthesis is reversibly inhibited when cells are exposed to hypertonic medium. However, it has been reported that initiation of virus-specific protein synthesis is more resistant to a hypertonic initiation block (Carrasco and Smith, 1976). Carrasco (1977) also showed that treatment of encephalomyocarditis virus-infected HeLa cells with hypertonic medium stimulated the synthesis of virus-specific proteins and proposed that insertion of viral proteins into the cell membrane altered the ionic conditions within the cell to favor viral protein synthesis. The Carrasco hypothesis has been shown to apply to many cytolytic infections by animal viruses, although there are a few exceptions (Fenwick and Walker, 1978 Gray et al., 1983). 

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