ERK1/2 Controls Na,K-ATPase Activity and Transepithelial Sodium Transport in the Principal Cell of the Cortical Collecting Duct of the Mouse Kidney

Prostaglandin E2 (PGE2) is the most abundant prostanoid in the kidney, affecting a wide range of renal functions. Conflicting data have been reported regarding the effects of PGE2 on tubular water and ion transport. The amiloride-sensitive epithelial sodium channel (ENaC) is rate limiting for transepithelial sodium transport in the aldosterone-sensitive distal nephron. The aim of the present study was to explore a potential role of PGE2 in regulating ENaC in cortical collecting duct (CCD) cells. Short-circuit current (ISC) measurements were performed using the murine mCCDcl1 cell line known to express characteristic properties of CCD principal cells and to be responsive to physiological concentrations of aldosterone and vasopressin. PGE2 stimulated amiloride-sensitive ISC via basolateral prostaglandin E receptors type 4 (EP4) with an EC50 of ∼7.1 nM. The rapid stimulatory effect of PGE2 on ISC resembled that of vasopressin. A maximum response was reached within minutes, coinciding with an increased abundance of β-ENaC at the apical plasma membrane and elevated cytosolic cAMP levels. The effects of PGE2 and vasopressin were nonadditive, indicating similar signaling cascades. Exposing mCCDcl1 cells to aldosterone caused a much slower (∼2 h) increase of the amiloride-sensitive ISC. Interestingly, the rapid effect of PGE2 was preserved even after aldosterone stimulation. Furthermore, application of arachidonic acid also increased the amiloride-sensitive ISC involving basolateral EP4 receptors. Exposure to arachidonic acid resulted in elevated PGE2 in the basolateral medium in a cyclooxygenase 1 (COX-1)–dependent manner. These data suggest that in the cortical collecting duct, locally produced and secreted PGE2 can stimulate ENaC-mediated transepithelial sodium transport.

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Potassium depletion increases proton pump (H+-ATPase) activity in intercalated cells of cortical collecting duct

AJP Renal Physiology ◽

10.1152/ajprenal.2000.279.1.f195 ◽

2000 ◽

Vol 279 (1) ◽

pp. F195-F202 ◽

Cited By ~ 21

Author(s):

Randi B. Silver ◽

Sylvie Breton ◽

Dennis Brown

Keyword(s):

Plasma Membrane ◽

Atpase Activity ◽

Collecting Duct ◽

Proton Pumps ◽

Intercalated Cells ◽

Cortical Collecting Duct ◽

Collecting Ducts ◽

Acid Load ◽

Collecting Tubules ◽

Atpase Staining

Intercalated cells (ICs) from kidney collecting ducts contain proton-transporting ATPases (H+-ATPases) whose plasma membrane expression is regulated under a variety of conditions. It has been shown that net proton secretion occurs in the distal nephron from chronically K+-depleted rats and that upregulation of tubular H+- ATPase is involved in this process. However, regulation of this protein at the level of individual cells has not so far been examined. In the present study, H+-ATPase activity was determined in individually identified ICs from control and chronically K+-depleted rats (9–14 days on a low-K+ diet) by monitoring K+- and Na+-independent H+ extrusion rates after an acute acid load. Split-open rat cortical collecting tubules were loaded with the intracellular pH (pHi) indicator 2′,7′-bis(2-carboxyethyl)-5(6)-carboxyfluorescein, and pHiwas determined by using ratiometric fluorescence imaging. The rate of pHi recovery in ICs in response to an acute acid load, a measure of plasma membrane H+-ATPase activity, was increased after K+ depletion to almost three times that of controls. Furthermore, the lag time before the start of pHirecovery after the cells were maximally acidified fell from 93.5 ± 13.7 s in controls to 24.5 ± 2.1 s in K+-depleted rats. In all ICs tested, Na+- and K+-independent pHi recovery was abolished in the presence of bafilomycin (100 nM), an inhibitor of the H+-ATPase. Analysis of the cell-to-cell variability in the rate of pHi recovery reveals a change in the distribution of membrane-bound proton pumps in the IC population of cortical collecting duct from K+-depleted rats. Immunocytochemical analysis of collecting ducts from control and K+-depleted rats showed that K+-depletion increased the number of ICs with tight apical H+ATPase staining and decreased the number of cells with diffuse or basolateral H+-ATPase staining. Taken together, these data indicate that chronic K+ depletion induces a marked increase in plasma membrane H+ATPase activity in individual ICs.

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IGF-1 vs insulin: Respective roles in modulating sodium transport via the PI-3 kinase/Sgk1 pathway in a cortical collecting duct cell line

Kidney International ◽

10.1038/sj.ki.5002018 ◽

2007 ◽

Vol 71 (2) ◽

pp. 116-125 ◽

Cited By ~ 43

Author(s):

E. Gonzalez-Rodriguez ◽

H.-P. Gaeggeler ◽

B.C. Rossier

Keyword(s):

Cell Line ◽

Sodium Transport ◽

Collecting Duct ◽

Duct Cell ◽

Cortical Collecting Duct

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Intracellular Na+ Controls Cell Surface Expression of Na,K-ATPase via a cAMP-independent PKA Pathway in Mammalian Kidney Collecting Duct Cells

Molecular Biology of the Cell ◽

10.1091/mbc.e02-11-0720 ◽

2003 ◽

Vol 14 (7) ◽

pp. 2677-2688 ◽

Cited By ~ 49

Author(s):

Manlio Vinciguerra ◽

Georges Deschênes ◽

Udo Hasler ◽

David Mordasini ◽

Martine Rousselot ◽

...

Keyword(s):

Cell Membrane ◽

Cell Surface ◽

Atpase Activity ◽

Collecting Duct ◽

Surface Expression ◽

Cell Surface Expression ◽

Cortical Collecting Duct ◽

Mammalian Kidney ◽

Duct Cells ◽

Collecting Duct Cells

In the mammalian kidney the fine control of Na+ reabsorption takes place in collecting duct principal cells where basolateral Na,K-ATPase provides the driving force for vectorial Na+ transport. In the cortical collecting duct (CCD), a rise in intracellular Na+ concentration ([Na+]i) was shown to increase Na,K-ATPase activity and the number of ouabain binding sites, but the mechanism responsible for this event has not yet been elucidated. A rise in [Na+]i caused by incubation with the Na+ ionophore nystatin, increased Na,K-ATPase activity and cell surface expression to the same extent in isolated rat CCD. In cultured mouse mpkCCDcl4 collecting duct cells, increasing [Na+]i either by cell membrane permeabilization with amphotericin B or nystatin, or by incubating cells in a K+-free medium, also increased Na,K-ATPase cell surface expression. The [Na+]i-dependent increase in Na,K-ATPase cell-surface expression was prevented by PKA inhibitors H89 and PKI. Moreover, the effects of [Na+]i and cAMP were not additive. However, [Na+]i-dependent activation of PKA was not associated with an increase in cellular cAMP but was prevented by inhibiting the proteasome. These findings suggest that Na,K-ATPase may be recruited to the cell membrane following an increase in [Na+]i through cAMP-independent PKA activation that is itself dependent on proteasomal activity.

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Nitric oxide inhibits bafilomycin-sensitive H(+)-ATPase activity in rat cortical collecting duct

AJP Renal Physiology ◽

10.1152/ajprenal.1994.267.4.f509 ◽

1994 ◽

Vol 267 (4) ◽

pp. F509-F515 ◽

Cited By ~ 13

Author(s):

A. Tojo ◽

N. J. Guzman ◽

L. C. Garg ◽

C. C. Tisher ◽

K. M. Madsen

Keyword(s):

Nitric Oxide ◽

Atpase Activity ◽

Ph Regulation ◽

Collecting Duct ◽

Competitive Inhibitor ◽

No Production ◽

Intercalated Cells ◽

Cortical Collecting Duct ◽

Dose Dependent Decrease ◽

Nos Isoforms

Nitric oxide (NO) is a messenger molecule that is produced from L-arginine by NO synthase (NOS). Some NOS isoforms are present in cells constitutively, whereas others can be induced by cytokines. Recent evidence suggests that NO inhibits intracellular pH regulation by the vacuolar H(+)-adenosinetriphosphatase (ATPase) in macrophages, which contain an inducible form of NOS. The vacuolar H(+)-ATPase is involved in proton secretion in intercalated cells in the collecting duct. We have therefore examined the effect of NO on bafilomycin-sensitive H(+)-ATPase activity in individual cortical collecting ducts (CCD) microdissected from collagenase-treated kidneys of normal rats using a fluorometric microassay. Incubation of CCD with the NO donors, sodium nitroprusside (0.1 and 1 mM) or 3-morpholino-sydnonimine hydrochloride (SIN-1, 30 microM), caused a dose-dependent decrease in H(+)-ATPase activity. Incubation of CCD with lipopolysaccharide (LPS) and interferon-gamma, which induces NOS in macrophages, decreased H(+)-ATPase activity by 85%. This effect was prevented by simultaneous incubation with N omega-nitro-L-arginine, a competitive inhibitor of NOS, indicating that the decrease in H(+)-ATPase activity was caused by NO production. Incubation with 8-bromo-guanosine 3',5'-cyclic monophosphate (cGMP) also inhibited H(+)-ATPase activity, suggesting that NO may exert its effect in the CCD via activation of guanylyl cyclase and production of cGMP. Immunohistochemistry using antibodies to the macrophage-type NOS revealed strong labeling of intercalated cells in the CCD, confirming the presence of NOS in these cells.(ABSTRACT TRUNCATED AT 250 WORDS)

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Time-dependent actions of aldosterone and amiloride on Na+-K+-ATPase of cortical collecting duct

AJP Renal Physiology ◽

10.1152/ajprenal.1988.254.5.f689 ◽

1988 ◽

Vol 254 (5) ◽

pp. F689-F696 ◽

Cited By ~ 7

Author(s):

R. A. Hayhurst ◽

R. G. O'Neil

Keyword(s):

Atpase Activity ◽

Latent Period ◽

Collecting Duct ◽

Constant Infusion ◽

Kinetic Properties ◽

Cortical Collecting Duct ◽

Initial Activity ◽

Simultaneous Treatment ◽

Single Mechanism ◽

Variable Modulation

The actions of aldosterone on Vmax Na+-K+-ATPase activity and length of latent period were assessed for the rabbit cortical collecting duct (CCD). Initially, animals were moderately aldosterone depleted and then treated with a constant infusion of physiological doses of aldosterone. Aldosterone administration had no influence after 3 h but caused a detectable increase with 6 (borderline significance) or more hours. An apparent plateau was reached between 24 and 48 h at twice the initial activity. This aldosterone-induced stimulation could be abolished by simultaneous treatment of the animals with amiloride, demonstrating a Na+-dependent modulation of the Vmax Na+-K+-ATPase activity. The aldosterone-stimulated enzyme had kinetic properties similar to those reported by others, but the latent period for aldosterone action on the Vmax Na+-K+-ATPase activity averaged near 6 h in the present study, as opposed to the highly variable period (from 1 h to several days) seen by others. This latent period variability was shown to be directly related to the initial Vmax Na+-K+-ATPase activity in the CCD and could be likened to an "end product dependent" latent period, i.e., the lower the initial end product (Vmax Na+-K+-ATPase activity) the shorter the latent period. Hence aldosterone's actions on the Na+-K+-ATPase of the CCD would be consistent with a single mechanism of action, i.e., increased synthesis, but with a variable modulation of this synthesis, which is dependent on the initial Vmax Na+-K+-ATPase activity of the CCD cells and/or the initial aldosterone status of the animal.

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Transcriptome of a mouse kidney cortical collecting duct cell line: Effects of aldosterone and vasopressin

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.051603198 ◽

2001 ◽

Vol 98 (5) ◽

pp. 2712-2716 ◽

Cited By ~ 157

Author(s):

M. Robert-Nicoud ◽

M. Flahaut ◽

J.-M. Elalouf ◽

M. Nicod ◽

M. Salinas ◽

...

Keyword(s):

Cell Line ◽

Collecting Duct ◽

Duct Cell ◽

Mouse Kidney ◽

Cortical Collecting Duct

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Luminal flow modulates H+-ATPase activity in the cortical collecting duct (CCD)

AJP Renal Physiology ◽

10.1152/ajprenal.00179.2011 ◽

2012 ◽

Vol 302 (1) ◽

pp. F205-F215 ◽

Cited By ~ 13

Author(s):

Wen Liu ◽

Núria M. Pastor-Soler ◽

Carlos Schreck ◽

Beth Zavilowitz ◽

Thomas R. Kleyman ◽

...

Keyword(s):

Atpase Activity ◽

Collecting Duct ◽

Axial Flow ◽

Bk Channel ◽

Cortical Collecting Duct ◽

Dolichos Biflorus ◽

Intracellular Ca ◽

Acid Load ◽

Luminal Flow ◽

Principal And Intercalated Cells

Epithelial Na+ channel (ENaC)-mediated Na+ absorption and BK channel-mediated K+ secretion in the cortical collecting duct (CCD) are modulated by flow, the latter requiring an increase in intracellular Ca2+ concentration ([Ca2+]i), microtubule integrity, and exocytic insertion of preformed channels into the apical membrane. As axial flow modulates HCO3− reabsorption in the proximal tubule due to changes in both luminal Na+/H+ exchanger 3 and H+-ATPase activity (Du Z, Yan Q, Duan Y, Weinbaum S, Weinstein AM, Wang T. Am J Physiol Renal Physiol 290: F289–F296, 2006), we sought to test the hypothesis that flow also regulates H+-ATPase activity in the CCD. H+-ATPase activity was assayed in individually identified cells in microperfused CCDs isolated from New Zealand White rabbits, loaded with the pH-sensitive dye BCECF, and then subjected to an acute intracellular acid load (NH4Cl prepulse technique). H+-ATPase activity was defined as the initial rate of bafilomycin-inhibitable cell pH (pHi) recovery in the absence of luminal K+, bilateral Na+, and CO2/HCO3−, from a nadir pH of ∼6.2. We found that 1) an increase in luminal flow rate from ∼1 to 5 nl·min−1·mm−1 stimulated H+-ATPase activity, 2) flow-stimulated H+ pumping was Ca2+ dependent and required microtubule integrity, and 3) basal and flow-stimulated pHi recovery was detected in cells that labeled with the apical principal cell marker rhodamine Dolichos biflorus agglutinin as well as cells that did not. We conclude that luminal flow modulates H+-ATPase activity in the rabbit CCD and that H+-ATPases therein are present in both principal and intercalated cells.

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