Hyperosmotic response

Kim NS, Lee GM (2002), Response of recombinant Chinese hamster ovary cells to hyperosmotic pressure effect of Bcl-2 overexpression, J. Biotechnol. 95 237-248. 

The second event in this initial phase of the response of E. coli to hyperosmotic stress is the synthesis of glutamate, which replaces Cr as a counterion to K+ (figure 6.15). Increased synthesis of glutamate occurs quickly, usually within a minute of exposure to hyperosmotic stress, but it cannot occur until the initial rise in concentration of intracellular K+ has taken place. 

Ferarris, J.D., C.K. Williams, K.-Y. Jung, J.J. Bedford, M.B. Burg, and A. Garcia-Perez (1996). ORE, a eukaryotic minimal essential osmotic response element the aldose reductase gene in hyperosmotic stress. J. Biol. Chem. 271 18318-18321. 

Stimuli for Drinking. Thirst stimulation and the act of drinking are basic physiological responses. The three major circumstances known to stimulate thirst and drinking are (1) a deficit of body water (hypohydration and hypovolemia), (2) an increase in the osmolality of the extracellular fluid volume (hyperosmolality and hyperosmotemia), and (3) consumption of dry food (prandial thirst) (50). These three factors can function independently, but they are often interactive e.g., a hypovolemic subject is often hyperosmotic. In addition, the hormone angiotensin II acts as a stimulant for drinking (dipsogen) in animals, and possibly in man (51). 

Drbak, B.K., and Watkins, P.A., 2000, Inositol(l,4,5)trisphosphate production in plant cells an early response to salinity and hyperosmotic stress. FEBS Lett. 481 240-244. 

Cho, M.H., Shears, S.B. and Boss, W.F., 1993, Changes in phosphatidylinositol metabolism in response to hyperosmotic stress in Daucus carota L. cells grown in suspension culture. Plant Physiol. 103 637-647. 

Furthermore, phosphoinositide/inositol phosphate turnover plays an important role in the production of secondary messengers during abiotic stress in plants. Within a few seconds, hyperosmotic shock induced a rapid and transient increase of Ins( 1,4,5)P3 in Arabidopsis cultured cells. This fact strongly suggests the PI turnover system functions near an osmosensor however, the molecule that functions as the osmosensor has not been identified, except in yeast and bacteria. In the near future, we hope to determine which molecule can activate the PI turnover system in response to hyperosmotic stress in plants. 

It is clinically useful to consider corneal edema as epithelial, stromal, or a combination of both. In general, epithelial edema is more responsive to topical hyperosmotic therapy. 

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