1997
Intracellular acidosis activates c-Src
Yamaji Y, Tsuganezawa H, Moe OW, Alpern RJ. Intracellular acidosis activates c-Src. American Journal Of Physiology 1997, 272: c886-c893. PMID: 9124524, DOI: 10.1152/ajpcell.1997.272.3.c886.Peer-Reviewed Original ResearchConceptsC-SrcC-Src activationProtein tyrosine phosphatase inhibitorProtein tyrosine kinase pathwaysMedium acidificationTyrosine phosphatase inhibitorProtein tyrosine phosphorylationC-Src activityTyrosine kinase pathwayPhosphatase inhibitorPhosphotyrosine contentCell pH changesTyrosine phosphorylationCytosolic proteinsKinase pathwayRenal proximal tubule cell lineCellular responsesSodium orthovanadateNovel mechanismProximal tubule cell lineCell linesTubule cell lineCell acidificationSignificant activationActivation
1995
Na+/H+ antiporter (NHE-1 isoform) in cultured vascular smooth muscle from the spontaneously hypertensive rat
LaPointe M, Ye M, Moe O, Alpern R, Batlle D. Na+/H+ antiporter (NHE-1 isoform) in cultured vascular smooth muscle from the spontaneously hypertensive rat. Kidney International 1995, 47: 78-87. PMID: 7731174, DOI: 10.1038/ki.1995.9.Peer-Reviewed Original ResearchConceptsVascular smooth muscle cellsCultured aortic vascular smooth muscle cellsWistar/Kyoto ratsAortic vascular smooth muscle cellsWKY ratsHypertensive ratsNominal absenceCultured vascular smooth muscleVascular smooth muscleSmooth muscle cellsCell acidificationRate of intracellularNormotensive controlsKyoto ratsNHE-1 isoformWKY cellsSmooth muscleSHRHigh functional activityRatsMuscle cellsThymidine incorporationPresence of HCO3Exchange activityHCO3-/CO2
1993
Cyclic adenosine monophosphate acutely inhibits and chronically stimulates Na/H antiporter in OKP cells.
Cano A, Preisig P, Alpern RJ. Cyclic adenosine monophosphate acutely inhibits and chronically stimulates Na/H antiporter in OKP cells. Journal Of Clinical Investigation 1993, 92: 1632-1638. PMID: 7691881, PMCID: PMC288321, DOI: 10.1172/jci116748.Peer-Reviewed Original ResearchConceptsNa/H antiporter activityRenal Na excretionNa excretionNa/H antiporterOKP cellsH antiporterAntiporter activityAddition of forskolinParathyroid hormoneAngiotensin IIAcute effectsChronic increaseChronic activationCyclic adenosine monophosphateChronic effectsChronic applicationNonspecific effectsPersistent activationPersistent increaseAlpha-adrenergic catecholaminesCell cAMPEndogenous generationAdenosine monophosphateH exposureCell acidification
1991
Inhibition of Na(+)-independent H+ pump by Na(+)-induced changes in cell Ca2+.
Hays SR, Alpern RJ. Inhibition of Na(+)-independent H+ pump by Na(+)-induced changes in cell Ca2+. The Journal Of General Physiology 1991, 98: 791-813. PMID: 1660062, PMCID: PMC2229082, DOI: 10.1085/jgp.98.4.791.Peer-Reviewed Original ResearchConceptsCell pH recoveryCell Ca2PH recoveryAcid loadPump activityRenal outer medullaryDelayed activationCell acidificationRapid cell acidificationUnits/minApical membraneCell pHSustained elevationFura-2Outer medullaryExtracellular Ca2Inner stripeIntracellular Ca2Steady-state cell pHSustained increaseDimethyl-BAPTAInitial suppressionSpike increasePhysiologic ratesMicrofilament-disrupting agentIncreased Na/H antiporter and Na/3HCO3 symporter activities in chronic hyperfiltration. A model of cell hypertrophy.
Preisig PA, Alpern RJ. Increased Na/H antiporter and Na/3HCO3 symporter activities in chronic hyperfiltration. A model of cell hypertrophy. The Journal Of General Physiology 1991, 97: 195-217. PMID: 1849958, PMCID: PMC2216475, DOI: 10.1085/jgp.97.2.195.Peer-Reviewed Original ResearchConceptsHyperfiltration groupChronic hyperfiltrationNa/H antiporterKidney weightCell hypertrophyHigher glomerular filtration rateNa/H antiporter activityH antiporterGlomerular filtration rateVivo microperfused rat proximal tubuleCell pHRat proximal tubuleSymporter activityFiltration rateProximal tubulesUltrafiltrate-like solutionHyperfiltrationSteady-state cell pHProtein feedingPeritubular perfusateDietary proteinParallel increaseUninephrectomyHypertrophyCell acidification
1990
Apical and basolateral membrane H+ extrusion mechanisms in inner stripe of rabbit outer medullary collecting duct
Hays SR, Alpern RJ. Apical and basolateral membrane H+ extrusion mechanisms in inner stripe of rabbit outer medullary collecting duct. American Journal Of Physiology 1990, 259: f628-f635. PMID: 2171359, DOI: 10.1152/ajprenal.1990.259.4.f628.Peer-Reviewed Original ResearchConceptsUnits/minPHi recoveryInner stripeAcid loadInitial control levelsSCH 28080Luminal Sch-28080ATPase inhibitorBasolateral membraneTriphasic responseExtrusion mechanismSlow alkalinizationRate of alkalinizationControl levelsCell acidificationRabbitsInhibitorsDuctTotal absenceInitial rateAlkalinizationN-ethylmaleimideRecoveryMinPreincubation in acid medium increases Na/H antiporter activity in cultured renal proximal tubule cells.
Horie S, Moe O, Tejedor A, Alpern RJ. Preincubation in acid medium increases Na/H antiporter activity in cultured renal proximal tubule cells. Proceedings Of The National Academy Of Sciences Of The United States Of America 1990, 87: 4742-4745. PMID: 2162055, PMCID: PMC54193, DOI: 10.1073/pnas.87.12.4742.Peer-Reviewed Original ResearchConceptsNa/H antiporter activityProximal tubule cellsTubule cellsCultured renal proximal tubule cellsCultured proximal tubule cellsRenal proximal tubule cellsPreincubation of fibroblastsExtracellular fluidAntiporter activityChronic acidosisAcidotic environmentCO2/HCO3Small inhibitionPreincubationPreincubation mediumAddition of cycloheximideCell acidificationAcid preincubationPresent studyProtein synthesisCellsAcidosisActivityEpitheliumBasolateral membrane Na(+)-independent Cl-/HCO3- exchange in the inner stripe of the rabbit outer medullary collecting tubule.
Hays SR, Alpern RJ. Basolateral membrane Na(+)-independent Cl-/HCO3- exchange in the inner stripe of the rabbit outer medullary collecting tubule. The Journal Of General Physiology 1990, 95: 347-367. PMID: 2307960, PMCID: PMC2216319, DOI: 10.1085/jgp.95.2.347.Peer-Reviewed Original ResearchConceptsInner stripePeritubular ClDistal nephron segmentsBasolateral membraneCell acidificationCell pHLuminal changesUrinary acidificationNephron segmentsPH-sensitive fluorescent dyeIndependent ClCell alkalinizationCO2/HCO3Peritubular pHVoltage clampTubulesTwo-thirdsRabbitsTotal replacementCell pH changes
1987
Basolateral membrane Na/base cotransport is dependent on CO2/HCO3 in the proximal convoluted tubule.
Krapf R, Alpern RJ, Rector FC, Berry CA. Basolateral membrane Na/base cotransport is dependent on CO2/HCO3 in the proximal convoluted tubule. The Journal Of General Physiology 1987, 90: 833-853. PMID: 2831294, PMCID: PMC2228880, DOI: 10.1085/jgp.90.6.833.Peer-Reviewed Original Research
1985
Mechanism of basolateral membrane H+/OH-/HCO-3 transport in the rat proximal convoluted tubule. A sodium-coupled electrogenic process.
Alpern RJ. Mechanism of basolateral membrane H+/OH-/HCO-3 transport in the rat proximal convoluted tubule. A sodium-coupled electrogenic process. The Journal Of General Physiology 1985, 86: 613-636. PMID: 2999293, PMCID: PMC2228817, DOI: 10.1085/jgp.86.5.613.Peer-Reviewed Original ResearchConceptsUnits/minPeritubular pHHigh extracellular potassium concentrationCell pHSodium concentrationPotassium concentrationExtracellular potassium concentrationBasolateral membranePeritubular potassium concentrationCell depolarizationMeq/Sodium removalCell acidificationTubulesPeritubular fluidTotal absenceSitCellsRatsMinSodium