Document Detail


Loss of cell volume regulation during metabolic inhibition in renal epithelial cells (A6): role of intracellular pH.
MedLine Citation:
PMID:  12107063     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
In renal ischemia, tubular obstruction induced by swelling of epithelial cells might be an important mechanism for reduction of the glomerular filtration rate. We investigated ischemic cell swelling by examining volume regulation of A6 cells during metabolic inhibition (MI) induced by cyanide and 2-deoxyglucose. Changes in cell volume were monitored by recording cell thickness (T(c)). Intracellular pH (pH(c)) measurements were performed with the pH-sensitive probe 5-chloromethyl-fluoresceine diacetate. T(c) measurements showed that MI increases cell volume. Cell swelling during MI is proportional to the rate of Na(+) transport and is not followed by a volume regulatory response. Furthermore, MI prevents the regulatory volume decrease (RVD) elicited by a hyposmotic shock. MI induces a pronounced intracellular acidification that is conserved during a subsequent hypotonic shock. A transient acidification induced by a NH(4)Cl prepulse causes a marked delay of the RVD in response to a hypotonic shock. On the other hand, acute lowering of external pH to 5, simultaneously with the hypotonic shock, allowed the onset of RVD. However, this RVD was completely arrested approximately 10 min after the initiation of the hyposmotic challenge. The inhibition of RVD appears to be related to the pronounced acidification that occurred within this time period. In contrast, when external pH was lowered 20 min before the hyposmotic shock, RVD was absent. These data suggest that internal acidification inhibits cellular volume regulation in A6 cells. Therefore, the intracellular acidification associated with MI might at least partly account for the failure of volume regulation in swollen epithelial cells.
Authors:
Ilse Smets; Marcel Ameloot; Paul Steels; Willy Van Driessche
Related Documents :
5344103 - Mechanism of optical effects in suspensions of a marine pseudomonad.
10854713 - Volume-sensitive amino acid efflux from a pancreatic beta-cell line.
10068633 - Krox-20 controls scip expression, cell cycle exit and susceptibility to apoptosis in de...
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  American journal of physiology. Cell physiology     Volume:  283     ISSN:  0363-6143     ISO Abbreviation:  Am. J. Physiol., Cell Physiol.     Publication Date:  2002 Aug 
Date Detail:
Created Date:  2002-07-10     Completed Date:  2002-08-08     Revised Date:  2003-11-14    
Medline Journal Info:
Nlm Unique ID:  100901225     Medline TA:  Am J Physiol Cell Physiol     Country:  United States    
Other Details:
Languages:  eng     Pagination:  C535-44     Citation Subset:  IM    
Affiliation:
Laboratory of Physiology, Limburgs Universitair Centrum, Universitaire Campus Gebouw D, B-3590 Diepenbeek, Belgium.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Acids / metabolism
Amiloride / analogs & derivatives*,  pharmacology
Ammonium Chloride / pharmacology
Animals
Antimetabolites / pharmacology*
Biological Transport
Cell Line
Deoxyglucose / pharmacology
Epithelial Cells / cytology,  metabolism
Hydrogen-Ion Concentration
Hypotonic Solutions / pharmacology
Intracellular Membranes / metabolism
Kidney / cytology*,  drug effects,  metabolism*
Sodium / metabolism
Sodium Cyanide / pharmacology
Chemical
Reg. No./Substance:
0/Acids; 0/Antimetabolites; 0/Hypotonic Solutions; 1154-25-2/ethylisopropylamiloride; 12125-02-9/Ammonium Chloride; 143-33-9/Sodium Cyanide; 154-17-6/Deoxyglucose; 2609-46-3/Amiloride; 7440-23-5/Sodium

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Stressful preconditioning and HSP70 overexpression attenuate proteotoxicity of cellular ATP depletio...
Next Document:  GSK-3beta negatively regulates skeletal myotube hypertrophy.