Abstract
Renal tubular citrate transport is accomplished by electrogenic Na + coupled dicarboxylate transporter NaDC-1, a carrier subjected to regulation by acidosis. Trafficking of the Na+/H+ exchanger NHE3 is controlled by NHE regulating factors NHERF-1 and NHERF-2 and the serum and glucocorticoid inducible kinase SGK1. To test for a possible involvement in NaDC-1 regulation, mRNA encoding NaDC-1 was injected into Xenopus oocytes with or without cRNA encoding NHERF-1, NHERF-2, SGK1, SGK2, SGK3, and/or the constitutively active form of the related protein kinase B (T308,S473DPKB). Succinate induced inward currents (I succ) were taken as a measure of transport rate. Coexpression of neither NHERF-1 nor NHERF-2 in NaDC-1 expressing oocytes significantly altered Isucc. On the other hand, coexpression of SGK1, SGK3, and T308,S473DPKB stimulated Isucc, an effect further stimulated by additional coexpression of NHERF-2 but not of NHERF-1. The action of the kinases and NHERF-2 may link urinary citrate excretion to proximal tubular H+ secretion.
Original language | English |
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Pages (from-to) | 998-1003 |
Number of pages | 6 |
Journal | Biochemical and Biophysical Research Communications |
Volume | 313 |
Issue number | 4 |
DOIs | |
Publication status | Published - 23 Jan 2004 |
Keywords
- Alkalosis
- Citrate
- Insulin
- Kidney
- Na/H exchanger
- Proximal tubule
- Urolithiasis
ASJC Scopus subject areas
- Biophysics
- Biochemistry
- Molecular Biology
- Cell Biology