Abstract |
We examined the effects of human cytomegalovirus (HCMV) infection on the Na+-K+-Cl- cotransporter (NKCC) in a human fibroblast cell line. Using the Cl--sensitive dye MQAE, we showed that the mock-infected MRC-5 cells express a functional NKCC. 1) Intracellular Cl- concentration ([Cl-]i) was significantly reduced from 53.4 +/- 3.4 mM to 35.1 +/- 3.6 mM following bumetanide treatment. 2) Net Cl- efflux caused by replacement of external Cl- with gluconate was bumetanide sensitive. 3) In Cl--depleted mock-infected cells, the Cl- reuptake rate (in HCO-3-free media) was reduced in the absence of external Na+ and by treatment with bumetanide. After HCMV infection, we found that although [Cl-]i increased progressively [24 h postexposure (PE), 65.2 +/- 4.5 mM; 72 h PE, 80.4 +/- 5.0 mM], the bumetanide and Na+ sensitivities of [Cl-]i and net Cl- uptake and loss were reduced by 24 h PE and abolished by 72 h PE. Western blots using the NKCC-specific monoclonal antibody T4 showed an approximately ninefold decrease in the amount of NKCC protein after 72 h of infection. Thus HCMV infection resulted in the abolition of NKCC function coincident with the severe reduction in the amount of NKCC protein expressed.
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Authors | L M Maglova, W E Crowe, P R Smith, A A Altamirano, J M Russell |
Journal | The American journal of physiology
(Am J Physiol)
Vol. 275
Issue 5
Pg. C1330-41
(11 1998)
ISSN: 0002-9513 [Print] United States |
PMID | 9814982
(Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- Carrier Proteins
- Chlorides
- Coloring Agents
- Sodium-Potassium-Chloride Symporters
- Bumetanide
- Sodium
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Topics |
- Biological Transport
(drug effects)
- Bumetanide
(pharmacology)
- Carrier Proteins
(antagonists & inhibitors, biosynthesis, metabolism)
- Cell Line
- Chlorides
(metabolism)
- Coloring Agents
- Cytomegalovirus
(physiology)
- Cytomegalovirus Infections
- Embryo, Mammalian
- Fibroblasts
- Humans
- Kinetics
- Lung
- Sodium
(metabolism)
- Sodium-Potassium-Chloride Symporters
- Time Factors
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