| Coordinate regulation of organic osmolytes in renal cells. | |
| | |
MedLine Citation:
|
PMID: 8743477 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
Adaptation of cells to prolonged hypertonicity generally involves accumulation of compatible organic osmolytes. Renal medullary cells in vivo and in tissue culture accumulate several different organic osmolytes, including sorbitol, inositol, betaine, and glycerophosphocholine (GPC) in response to hypertonicity. For the total concentration of these organic osmolytes to be appropriate for the ambient tonicity, an increase in one should cause the others to fall, minimizing changes in their total concentration. The experiments presented here demonstrate this in tissue culture and investigate the mechanisms involved. Sorbitol is synthesized from glucose, catalyzed by aldose reductase. Betaine is transported into the cells. Hypertonicity increases transcription of the aldose reductase and betaine transporter genes, ultimately elevating cell sorbitol and betaine. If aldose reductase is inhibited, which prevents accumulation of sorbitol, betaine transporter gene expression increases, resulting in a higher cell betaine that compensates for the lower sorbitol. Conversely, when cell betaine is altered by changing its concentration in the medium, aldose reductase transcription changes reciprocally, resulting in compensating changes in cell sorbitol. Hypertonicity increases GPC by inhibiting GPC:choline phosphodiesterase (GPC:PDE), an enzyme that degrades GPC. When cell betaine or inositol is increased by raising its concentration in the medium, GPC:PDE activity rises, reducing cell GPC. Thus, the total of the osmolytes, rather than the level of any individual one, is maintained. |
| | |
Authors:
|
M B Burg |
Related Documents
:
|
1194237 - Physiological consequences of starvation in pseudomonas putida: degradation of intracel... 6331187 - Chloride transport properties of human leukemic cell lines k562 and hl60. 9030197 - Improved oligonucleotide uptake and stability by a new drug carrier, the supramolecular... 22487297 - Characterization of α-smooth muscle actin positive cells during multilineage different... 11256167 - Oocyte and embryo polarity. 2747267 - Morphometric analysis of chronic b-cell leukemias--an aid to the classification of lymp... |
Publication Detail:
|
Type: Journal Article; Review |
Journal Detail:
|
Title: Kidney international Volume: 49 ISSN: 0085-2538 ISO Abbreviation: Kidney Int. Publication Date: 1996 Jun |
Date Detail:
|
Created Date: 1996-11-15 Completed Date: 1996-11-15 Revised Date: 2005-11-16 |
Medline Journal Info:
|
Nlm Unique ID: 0323470 Medline TA: Kidney Int Country: UNITED STATES |
Other Details:
|
Languages: eng Pagination: 1684-5 Citation Subset: IM |
Affiliation:
|
National Heart, Lung and Blood Institute, Bethesda, Maryland, USA. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Animals Hypertonic Solutions / metabolism Kidney / cytology*, physiology Water-Electrolyte Balance / physiology* |
| Chemical | |
Reg. No./Substance:
|
0/Hypertonic Solutions |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Regulation of the myo-inositol and betaine cotransporters by tonicity.
Next Document: Osmoregulation in the renal papilla: membranes, messengers and molecules.