ATP-inhibitable Cl- channel in apical membranes of cultured rabbit cortical collecting duct cells

Excised patches of apical membranes from immunodissected rabbit cortical collecting duct cells in primary culture were studied by the patch-clamp technique. Barium (1 mM) and tetraethylammonium chloride (5 mM) were added to all solutions to block potassium channel activity. A unique channel was observed that exhibited inward rectification under symmetrical ionic conditions with a measured chord conductance of 54.0 +/- 2.5 pS at -80 mV (n = 11) and 22.1 +/- 1.7 pS at +80 mV (n = 5). This channel was chloride selective, with a PNa:PCl of 0.16 (n = 3). Kinetic analysis revealed a voltage-independent open-time probability of 0.80 +/- 0.07 (n = 6). Open-time probability within bursts was 0.96 +/- 0.01. Addition of ATP to the cytosolic surface of the channel resulted in a dose-dependent decrease in open probability, with a threshold effect at 10(-4) M, due to a reduction in burst open time. The effect of ATP was immediate, rapidly reversible at room temperature, and mimicked by GTP, adenosine 5'-O-(3-thiotriphosphate), and guanosine 5'-O-(3-thiotriphosphate). This channel may link epithelial chloride permeability to cellular ATP content in the rabbit cortical collecting duct.

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Whole cell sodium conductance of principal cells freshly isolated from rat cortical collecting duct

AJP Cell Physiology ◽

10.1152/ajpcell.1995.269.3.c791 ◽

1995 ◽

Vol 269 (3) ◽

pp. C791-C796 ◽

Cited By ~ 44

Author(s):

J. K. Bubien

Keyword(s):

Patch Clamp ◽

Collecting Duct ◽

Cortical Collecting Duct ◽

Patch Clamp Technique ◽

Whole Cell ◽

Cyclic Monophosphate ◽

Principal Cells ◽

Clamp Technique ◽

Duct Cells ◽

Collecting Duct Cells

Cortical collecting duct fragments were manually dissected from 6-wk-old Sprague-Dawley rats. The fragments were enzymatically digested (collagenase A) into single cells, washed, and resuspended in serum-free RPMI 1640. Individual cells were examined electrophysiologically using the whole cell patch-clamp technique. Two morphologically distinct cell types were present in the cell suspension. Small round cells that had a capacitance of 7 pF and larger oval cells with a capacitance of 29 pF were consistently observed. Whole cell electrophysiological examination revealed that the small round cells had virtually no plasma membrane ionic conductance, whereas both inward and outward currents were observed in the larger oval-type cells. Also, superfusion of 250 pM arginine vasopressin specifically increased the inward conductance of only the larger cells. The effect could be completely inhibited by 2 microM amiloride or 100 mumol of the Rp diastereomer of 8-(4-chlorophenylthio)-adenosine 3',5'-cyclic monophosphate (a specific adenosine 3',5'-cyclic monophosphate inhibitor). These findings are consistent with the hypothesis that the larger cells are principal cells and the smaller cells are intercalated cells and directly demonstrate that an amiloride-sensitive whole cell conductance is readily observable in freshly isolated cortical collecting duct cells. Thus the whole cell configuration of the patch-clamp technique appears to be well suited for assessing cellular mechanisms that regulate the ionic conductances of cortical collecting duct cells.

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Whole cell and unitary amiloride-sensitive sodium currents in M-1 mouse cortical collecting duct cells

AJP Cell Physiology ◽

10.1152/ajpcell.1996.270.4.c998 ◽

1996 ◽

Vol 270 (4) ◽

pp. C998-C1010 ◽

Cited By ~ 7

Author(s):

M. L. Chalfant ◽

T. G. O'Brien ◽

M. M. Civan

Keyword(s):

Collecting Duct ◽

Cell Permeability ◽

Na Channel ◽

Na Channels ◽

Cortical Collecting Duct ◽

Ionic Selectivity ◽

Whole Cell ◽

Duct Cells ◽

Excised Patches ◽

Collecting Duct Cells

Amiloride-sensitive whole cell currents have been reported in M-1 mouse cortical collecting duct cells (Korbmacher et al., J. Gen. Physiol. 102: 761-793, 1993). We have confirmed that amiloride inhibits the whole cell currents but not necessarily the measured whole cell currents. Anomalous responses were eliminated by removing external Na+ and/or introducing paraepithelial shunts. The amiloride-sensitive whole cell currents displayed Goldman rectification. The ionic selectivity sequence of the amiloride-sensitive conductance was Li+ > Na+ >> K+. Growth of M-1 cells on permeable supports increased the amiloride-sensitive whole cell permeability, compared with cells grown on plastic. Single amiloride-sensitive channels were observed, which conformed to the highly selective low-conductance amiloride-sensitive class [Na(5)] of epithelial Na+ channels. Hypotonic pretreatment markedly slowed run-down of channel activity. The gating of the M-1 Na+ channel in excised patches was complex. Open- and closed-state dwell-time distributions from patches that display one operative channel were best described with two or more exponential terms each. We conclude that 1) study of M-1 whole cell Na+ currents is facilitated by reducing the transepithelial potential to zero, 2) these M-1 currents reflect the operation of Na(5) channels, and 3) the Na+ channels display complex kinetics, involving > or = 2 open and > or = 2 closed states.

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Lipidomic and proteomic analysis of exosomes from mouse cortical collecting duct cells

The FASEB Journal ◽

10.1096/fj.201700417r ◽

2017 ◽

Vol 31 (12) ◽

pp. 5399-5408 ◽

Cited By ~ 28

Author(s):

Viet D. Dang ◽

Kishore Kumar Jella ◽

Ragy R. T. Ragheb ◽

Nancy D. Denslow ◽

Abdel A. Alli

Keyword(s):

Proteomic Analysis ◽

Collecting Duct ◽

Cortical Collecting Duct ◽

Duct Cells ◽

Collecting Duct Cells

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Protein Kinase D Stabilizes Aldosterone-Induced ERK1/2 MAP Kinase Activation in Renal M1 Cortical Collecting Duct Cells To Promote Cell Proliferation.

10.1210/endo-meetings.2010.part3.p13.p3-612 ◽

2010 ◽

pp. P3-612-P3-612

Author(s):

R Dooley ◽

V McEneaney ◽

BJ Harvey ◽

W Thomas

Keyword(s):

Cell Proliferation ◽

Protein Kinase ◽

Map Kinase ◽

Collecting Duct ◽

Protein Kinase D ◽

Cortical Collecting Duct ◽

Kinase Activation ◽

Promote Cell Proliferation ◽

Duct Cells ◽

Collecting Duct Cells

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Role of AQP2 during apoptosis in cortical collecting duct cells

Biology of the Cell ◽

10.1042/bc20080050 ◽

2009 ◽

Vol 101 (4) ◽

pp. 237-250 ◽

Cited By ~ 18

Author(s):

Pilar Flamenco ◽

Luciano Galizia ◽

Valeria Rivarola ◽

Juan Fernandez ◽

Paula Ford ◽

...

Keyword(s):

Collecting Duct ◽

Cortical Collecting Duct ◽

Duct Cells ◽

Collecting Duct Cells

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Mal protein stabilizes luminal membrane PLC-β3 and negatively regulates ENaC in mouse cortical collecting duct cells

AJP Renal Physiology ◽

10.1152/ajprenal.00446.2018 ◽

2019 ◽

Vol 317 (4) ◽

pp. F986-F995

Author(s):

Kubra M. Tuna ◽

Bing-Chen Liu ◽

Qiang Yue ◽

Zinah M. Ghazi ◽

He-Ping Ma ◽

...

Keyword(s):

Plasma Membrane ◽

Protein Expression ◽

Collecting Duct ◽

Renal Tubules ◽

Cortical Collecting Duct ◽

Open Probability ◽

Anionic Phospholipid ◽

Kinase Substrate ◽

Luminal Membrane ◽

Collecting Duct Cells

Abnormally high epithelial Na+ channel (ENaC) activity in the aldosterone-sensitive distal nephron and collecting duct leads to hypertension. Myelin and lymphocyte (Mal) is a lipid raft-associated protein that has been previously shown to regulate Na+-K-2Cl− cotransporter and aquaporin-2 in the kidney, but it is not known whether it regulates renal ENaC. ENaC activity is positively regulated by the anionic phospholipid phosphate phosphatidylinositol 4,5-bisphosphate (PIP2). Members of the myristoylated alanine-rich C-kinase substrate (MARCKS) family increase PIP2 concentrations at the plasma membrane, whereas hydrolysis of PIP2 by phospholipase C (PLC) reduces PIP2 abundance. Our hypothesis was that Mal protein negatively regulates renal ENaC activity by stabilizing PLC protein expression at the luminal plasma membrane. We investigated the association between Mal, MARCKS-like protein, and ENaC. We showed Mal colocalizes with PLC-β3 in lipid rafts and positively regulates its protein expression, thereby reducing PIP2 availability at the plasma membrane. Kidneys of 129Sv mice injected with MAL shRNA lentivirus resulted in increased ENaC open probability in split-open renal tubules. Overexpression of Mal protein in mouse cortical collecting duct (mpkCCD) cells resulted in an increase in PLC-β3 protein expression at the plasma membrane. siRNA-mediated knockdown of MAL in mpkCCD cells resulted in a decrease in PLC-β3 protein expression and an increase in PIP2 abundance. Moreover, kidneys from salt-loaded mice showed less Mal membrane protein expression compared with non-salt-loaded mice. Taken together, Mal protein may play an essential role in the negative feedback of ENaC gating in principal cells of the collecting duct.

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Amiloride-sensitive sodium channels in confluent M-1 mouse cortical collecting duct cells

The Journal of Membrane Biology ◽

10.1007/bf00207269 ◽

1995 ◽

Vol 148 (2) ◽

Cited By ~ 20

Author(s):

B. Letz ◽

A. Ackermann ◽

C.M. Canessa ◽

B.C. Rossier ◽

C. Korbmacher

Keyword(s):

Sodium Channels ◽

Collecting Duct ◽

Cortical Collecting Duct ◽

Duct Cells ◽

Collecting Duct Cells

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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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