Abstract
Stimulation of dopaminergic type 1 (D1) receptors increases lung edema clearance by regulating Na,K-ATPase function in the alveolar epithelium. We studied the role of serine/threonine protein phosphatases in the Na,K-ATPase regulation by D1 agonists in A549 cells. We found that low doses of the type 1/2A protein phosphatase inhibitor okadaic acid as well as SV40 small t antigen transiently transfected into A549 cells prevented the D1 agonist- induced increase in Na,K-ATPase activity and translocation from intracellular pools to the plasma membrane. This was associated with a rapid and transient increase in protein phosphatase 2A activity. We conclude that D1 stimulation regulates Na,K-ATPase activity by promoting recruitment of Na,K-ATPases from intracellular pools into the basolateral membranes of A549 cells via a type 2A protein phosphatase. (C) 2000 Federation of European Biochemical Societies.
Original language | English (US) |
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Pages (from-to) | 217-220 |
Number of pages | 4 |
Journal | FEBS Letters |
Volume | 481 |
Issue number | 3 |
DOIs | |
State | Published - Sep 22 2000 |
Funding
The authors wish to thank Dr. A. Bertorello, Dr. L. Dada, Dr. C. Guerrero, Dr. K. Ridge, and Dr. L. Pesce for valuable discussions, R. Vena for technical support, and Dr. E. Sontag for the small t expression plasmid. This research was supported in part by HL 65161 to J.I.S., the Department of Medicine, Northwestern University, and grants ARC 9449 and 9294 to A.G.
Keywords
- A549 cell
- D agonist
- Na,K-ATPase
- Protein phosphatase
ASJC Scopus subject areas
- Biophysics
- Structural Biology
- Biochemistry
- Molecular Biology
- Genetics
- Cell Biology