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, Uv (?l/g BW/ day)

S. Table, Clinical and urine parameters of Kcnj15 +/+ and Kcnj15 -/-mice under basal and acid-loading conditions. Parameters were mesured before (Day 0) and after 2 or 8 days of an oral 0.28 M NH 4 Cl-induced acid load, p.11

. Kcnj15--/-mice, Uv : urine volume. BW : body weight. * P < 0.05 vs Day 0 (paired Student's t test), ? P < 0.05 vs Kcnj15 +/+ mice at the given day

, Protein extraction. For western blot experiments, mouse kidneys snap-frozen into liquid

, After a centrifugation at 5,000 g for 10 minutes, protein content of supernatants was measured using the Pierce? BCA Protein Assay Kit

, Western blotting. 60 µg proteins were denaturated in a 2X Laemmli buffer containing

. %-?-mercapto-ethanol,

%. Sds, blocked using a TBS buffer supplemented with 5 % non-fat milk proteins and 0.2 % NP-40, then exposed to primary antibody, washed and finally exposed to the following HRP-conjugated secondary antibody: 170-6515 goat anti-rabbit, 10% polyacrylamide gels, transfered onto nitrocellulose membranes, vol.1

, The primary antibodies used were: APC-058 rabbit anti-Kir4.2, SPC-400D rabbit anti

, :1000 dilution), Cayman Chemical 10004943 rabbit anti-PEPCK (Bertin Bioreagent, dilution), APC-037 rabbit anti-TASK2 (Alomone Labs, 1:1000 dilution), vol.1, p.2500, 2000.

, The rabbit anti-PDG (1:5000 dilution) was kindly provided by Pr Javier Marquez (University of Malaga, Spain) Membrane potential measurement. Tubules were isolated from kidneys after a collagenase treatment as previously described, S5 then transferred into a chamber placed on the stage of an inverted microscope. The bath solution contained (mM) 130 NaCl, 20000.

. Na-acetate,-2-l-alanine, heat polished and backfilled with the bath solution. (Bio-Logic Science Instruments, Seyssinet-Pariset, France) set in the zero current-clamp (I0) mode was filtered at 50 Hz by a NPI Electronic LPBF-48DG low-pass 8-pole Bessel filter (Tamm, Germany) and digitized at a 100 Hz sampling rate by an Axon Instruments/Molecular Devices Digidata 1440A A/D converter and P-clamp software, HEPES, 10 glucose and was adjusted to pH 7.4 with tris(hydroxymethyl)aminoethane. Patch pipettes were pulled from thin-walled borosilicate glass capillaries, pp.20-25

, Intracellular pH measurements. Dye-loaded tubules were excited alternatively at 440

, BW 20 nm) every 2 seconds with an OptoLED light source (Cairn Research, Faversham, GB) and an iXon EMCCD camera (Andor Technology, vol.500

, 23 mM NaHCO 3 , 2 mM K 2 HPO 4 , 1.5 mM CaCl 2 , 1.2 mM MgSO 4 , 5 mM L-Alanine, 5.5 mM Dglucose and 10 mM HEPES) or a nominally Na + -free solution in which NMDG-Cl and NMDG-HCO 3 were substituted for NaCl and NaHCO 3, respectively. The tubular lumen was perfused with the Na + -free solution all, Proximal tubules were superfused with either a Na + -containing solution (119 mM NaCl

+. Na, H + exchanger to the intracellular pH responses. All solutions were continuously gassed with 95% O2/5% CO 2 (pH ~7.40) and kept at 37°C

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. S5, M. Paulais, S. Lachheb, and J. Teulon, A Na+-and Cl--activated K+ channel in the thick ascending limb of mouse kidney, J. Gen. Physiol, vol.127, pp.205-215, 2006.