2018
Prevention of Ischemic Injury in Colon and Small Intestine in an Ex Vivo Perfusion Animal Model
Finotti M, Lysyy T, Barahona M, Maina R, Caturegli G, D'Amico F, Mulligan D, Geibel J. Prevention of Ischemic Injury in Colon and Small Intestine in an Ex Vivo Perfusion Animal Model. Transplantation 2018, 102: s709. DOI: 10.1097/01.tp.0000543675.85457.d2.Peer-Reviewed Original ResearchIschemia-reperfusion injuryIschemic injuryIschemic damageL-arginineSmall intestineL-NAMEDistal colonPerfusion machineMale Sprague-Dawley ratsIntestinal ischemic damageIntestinal ischemic injuryAnti-ischemic effectsSprague-Dawley ratsIntestinal graftInflammatory injuryInflammatory pathwaysIntestinal viabilityProtective effectAbdominal cavityColon segmentsIschemic conditionsIntestinal wallIntraluminal secretionsAnimal modelsIntestine segments
2017
Acute Effects of Vitamin C Exposure On Colonic Crypts: Direct Modulation of pH Regulation
Aldajani MM, Vanicek CN, Alhazzaa N, Lysyy T, Agarwal R, Geibel JP. Acute Effects of Vitamin C Exposure On Colonic Crypts: Direct Modulation of pH Regulation. Cellular Physiology And Biochemistry 2017, 44: 377-387. PMID: 29132138, DOI: 10.1159/000484914.Peer-Reviewed Original ResearchConceptsVitamin CColonic cryptsAcute effectsDependent intracellular pH recoveryTumor formationIntracellular pH recoveryNew therapeutic agentsMM vitamin CColorectal cancerDistal colonLeading causeTranscellular passive diffusionBasolateral membraneAcute additionNormal colonic cryptsC exposureNutraceutical agentTherapeutic agentsPH recoveryIntracellular pH changesCancer cellsVitamin C.CryptsLow intracellularTight junctions
2013
Identification of Functionally Distinct Na-HCO3 Co-Transporters in Colon
Barmeyer C, Ye JH, Soroka C, Geibel P, Hingsammer LM, Weitgasser L, Atway D, Geibel JP, Binder HJ, Rajendran VM. Identification of Functionally Distinct Na-HCO3 Co-Transporters in Colon. PLOS ONE 2013, 8: e62864. PMID: 23690961, PMCID: PMC3653958, DOI: 10.1371/journal.pone.0062864.Peer-Reviewed Original ResearchConceptsNa-HCO3 cotransportDistal colonProximal colonNBC activityNBC isoformsRat colonColonic epithelial cellsCrypt glandsSensitive transporterHCO3- secretionColonHCO3-dependent mechanismEpithelial cellsSaturable processHOE694Isoform 1Basolateral membraneCotransportPCR analysisNorthern blotDIDSMolecular studiesMolecular identityApparent KiCritical role
2007
Characteristics of rat downregulated in adenoma (rDRA) expressed in HEK 293 cells
Barmeyer C, Ye JH, Sidani S, Geibel J, Binder HJ, Rajendran VM. Characteristics of rat downregulated in adenoma (rDRA) expressed in HEK 293 cells. Pflügers Archiv - European Journal Of Physiology 2007, 454: 441-450. PMID: 17492310, DOI: 10.1007/s00424-007-0213-7.Peer-Reviewed Original ResearchMeSH Keywords4,4'-Diisothiocyanostilbene-2,2'-Disulfonic AcidAmino Acid SequenceAnimalsAntiportersBase SequenceBicarbonatesCell LineChloridesCloning, MolecularColonDNA PrimersFatty Acids, VolatileHumansHydrogen-Ion ConcentrationIon TransportMolecular Sequence DataRatsRecombinant ProteinsSequence Homology, Amino AcidSulfate TransportersTransfectionConceptsRat distal colonDistal colonHEK-293 cellsExtracellular Cl- concentrationCrypt cellsMRNA expressionColonRatsDigestive tractCharacteristics of ratsAdenomasHigh rateDIDSCl- influxSurface cellsIntracellular acidApical membrane vesiclesCellsDisulfonic acidApical membraneCl- uptakePrior observationsUptakeLungJejunum
2005
Bicarbonate Secretion
Binder HJ, Rajendran V, Sadasivan V, Geibel JP. Bicarbonate Secretion. Journal Of Clinical Gastroenterology 2005, 39: s53-s58. PMID: 15758660, DOI: 10.1097/01.mcg.0000155521.81382.3a.Peer-Reviewed Original Research
2004
Extracellular polyamines regulate fluid secretion in rat colonic crypts via the extracellular calcium-sensing receptor
Cheng SX, Geibel JP, Hebert SC. Extracellular polyamines regulate fluid secretion in rat colonic crypts via the extracellular calcium-sensing receptor. Gastroenterology 2004, 126: 148-158. PMID: 14699496, DOI: 10.1053/j.gastro.2003.10.064.Peer-Reviewed Original ResearchConceptsCalcium-sensing receptorColonic epithelial cellsFluid secretionColonic cryptsCalcium-sensing receptor activationExtracellular calcium-sensing receptorEpithelial cellsIntracellular D-myo-inositolNormal postnatal developmentRat colonic cryptsExtracellular polyaminesDistal colonDistal colonic cryptsSecond messenger generationDistal colonic epithelial cellsGastrointestinal epitheliumSecond messenger accumulationPostnatal developmentReceptor activationExtracellular spermineIntact cryptsReceptorsColonocyte functionSecretionCrypts
2003
Characterization of Cl-HCO3 exchange in basolateral membrane of rat distal colon
Ikuma M, Geibel J, Binder HJ, Rajendran VM. Characterization of Cl-HCO3 exchange in basolateral membrane of rat distal colon. American Journal Of Physiology - Cell Physiology 2003, 285: c912-c921. PMID: 12826602, DOI: 10.1152/ajpcell.00396.2002.Peer-Reviewed Original ResearchConceptsRat distal colonCl-HCO3 exchangeDistal colonBasolateral membraneHalf-maximal inhibitory constantsBasolateral membrane vesiclesCl- channel blockerColonic epithelial cellsAbsence of HCO3Channel blockersRat colonic epithelial cellsCrypt preparationCrypt cellsExchange inhibitorCl-OH exchangeRemoval of ClColonEpithelial cellsAnion exchange inhibitorHCO3- gradientProtease inhibitorsK ionophorePresent studyInhibitory constantsProtease inhibitor cocktail
2001
Cloning and Expression of a Chloride-dependent Na+-H+ Exchanger*
Sangan P, Rajendran VM, Geibel JP, Binder HJ. Cloning and Expression of a Chloride-dependent Na+-H+ Exchanger*. Journal Of Biological Chemistry 2001, 277: 9668-9675. PMID: 11773056, DOI: 10.1074/jbc.m110852200.Peer-Reviewed Original ResearchMeSH KeywordsAmilorideAmino Acid SequenceAnimalsBlotting, NorthernCell LineChlorineCloning, MolecularColonDiureticsDNA, ComplementaryFibroblastsHydrogen-Ion ConcentrationIn Situ HybridizationMaleMolecular Sequence DataPhosphorylationProtein Structure, TertiaryRatsRats, Sprague-DawleyRNA, MessengerSequence Homology, Amino AcidSodiumSodium-Hydrogen Exchanger 1Sodium-Hydrogen ExchangersTime FactorsTissue DistributionConceptsRat distal colonDistal colonAmino acidsCrypt cellsExchange isoformsDietary sodium depletionColonic crypt cellsFull-length cDNACl- channel blockerColonic epithelial cellsN-terminal regionNorthern blot analysisSodium depletionChannel blockersNovel C-terminusPutative transmembranePS120 fibroblastsAcid loadDependent intracellularC-terminusNHE-1Epithelial cellsIsoform inhibitorAmiloride analoguesMultiple tissuesCharacterization of apical membrane Cl-dependent Na/H exchange in crypt cells of rat distal colon
Rajendran V, Geibel J, Binder H. Characterization of apical membrane Cl-dependent Na/H exchange in crypt cells of rat distal colon. AJP Gastrointestinal And Liver Physiology 2001, 280: g400-g405. PMID: 11171622, DOI: 10.1152/ajpgi.2001.280.3.g400.Peer-Reviewed Original ResearchConceptsRat distal colonNa/H exchangeCl- channel blockerDistal colonChannel blockersCrypt cellsIntracellular pH recoveryExchange inhibitor amilorideColonic epithelial cellsApical membrane vesiclesCrypt glandsHigh doseHOE 694NA depletionAcid loadExchange inhibitorInhibitor amiloridePH recoveryEpithelial cellsUptake 1NHE isoformsAnion exchange inhibitorBlockersColonNa uptake
2000
Cl‐Dependent Na‐H Exchange: A Novel Colonic Crypt Transport Mechanism
BINDER H, RAJENDRAN V, GEIBEL J. Cl‐Dependent Na‐H Exchange: A Novel Colonic Crypt Transport Mechanism. Annals Of The New York Academy Of Sciences 2000, 915: 43-53. PMID: 11193600, DOI: 10.1111/j.1749-6632.2000.tb05222.x.Peer-Reviewed Original Research
1999
Direct Effects of Dopamine on Colonic Mucosal pH: Implications for Tonometry
Winter D, O'Sullivan G, Harvey B, Geibel J. Direct Effects of Dopamine on Colonic Mucosal pH: Implications for Tonometry. Journal Of Surgical Research 1999, 83: 62-68. PMID: 10210644, DOI: 10.1006/jsre.1998.5561.Peer-Reviewed Original ResearchConceptsSodium-hydrogen exchangeSplanchnic perfusionIntestinal mucosaLow-dose dopamine infusionBeta-adrenergic receptor blockadeEffects of dopamineSprague-Dawley ratsIntracellular calcium concentrationHepes-buffered Ringer's solutionMucosal crypt cellsFree cytosolic calciumCalcium-sensitive probeSplanchnic vasodilatorTonometric dataDopamine infusionMucosal effectsReceptor blockadeShocked patientsProtein kinase C inhibitionDistal colonGastric mucosaMucosal pHPharmacological agentsDirect effectTonometric measurementsRole of Cl channels in Cl-dependent Na/H exchange
Rajendran V, Geibel J, Binder H. Role of Cl channels in Cl-dependent Na/H exchange. American Journal Of Physiology 1999, 276: g73-g78. PMID: 9886981, DOI: 10.1152/ajpgi.1999.276.1.g73.Peer-Reviewed Original ResearchConceptsNa/H exchangeCl- channel blockerChannel blockersMicroM DIDSNa/H exchange activityCystic fibrosis transmembrane conductance regulatorIntracellular pH recoveryRat distal colonCl- channelsH exchange activityDistal colonCrypt lumenCrypt cellsAcid loadExchange inhibitorApical membranePH recoveryCl(-) dependenceAnion exchange inhibitorCl- channel activityChannel activityBlockersH exchangePolyclonal antibodiesCl- conductance
1998
Role of Apical H-K Exchange and Basolateral K Channel in the Regulation of Intracellular pH in Rat Distal Colon Crypt Cells
Ikuma M, Binder H, Geibel J. Role of Apical H-K Exchange and Basolateral K Channel in the Regulation of Intracellular pH in Rat Distal Colon Crypt Cells. The Journal Of Membrane Biology 1998, 166: 205-212. PMID: 9843594, DOI: 10.1007/s002329900462.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsAntiportersBariumCell PolarityColonEpithelial CellsH(+)-K(+)-Exchanging ATPaseHomeostasisHydrogen-Ion ConcentrationIntestinal MucosaIntracellular FluidIon TransportMaleOuabainPotassiumPotassium ChannelsPotassium-Hydrogen AntiportersRatsRats, Sprague-DawleySodium-Potassium-Exchanging ATPaseCl−HCO3 and Cl−OH exchanges of basolateral membranes (BLM) regulate intracellular pH (pHi) in crypt cells of rat distal colon
Ikuma M, Geibel J, Binder H, Rajendran V. Cl−HCO3 and Cl−OH exchanges of basolateral membranes (BLM) regulate intracellular pH (pHi) in crypt cells of rat distal colon. Gastroenterology 1998, 114: a380. DOI: 10.1016/s0016-5085(98)81539-4.Peer-Reviewed Original ResearchDifferential localization of colonic H+-K+-ATPase isoforms in surface and crypt cells
Rajendran V, Singh S, Geibel J, Binder H. Differential localization of colonic H+-K+-ATPase isoforms in surface and crypt cells. American Journal Of Physiology 1998, 274: g424-g429. PMID: 9486199, DOI: 10.1152/ajpgi.1998.274.2.g424.Peer-Reviewed Original ResearchConceptsCrypt cellsColonic cryptsRat distal colonSurface cellsSurface epithelial cellsATPase isoformsOuabain-insensitive componentApical membraneDistal colonAcid loadDependent intracellularEpithelial cellsATPase activityCryptsDifferential localizationOuabainATPase alpha subunitCellsAlpha subunitCompelling evidenceIsoformsColonActivityRecovery
1997
Novel Transport Properties of Colonic Crypt Cells: Fluid Absorption and Cl-Dependent Na-H Exchange
Binder H, Singh S, Geibel J, Rajendran V. Novel Transport Properties of Colonic Crypt Cells: Fluid Absorption and Cl-Dependent Na-H Exchange. Comparative Biochemistry And Physiology Part A Molecular & Integrative Physiology 1997, 118: 265-269. PMID: 9366054, DOI: 10.1016/s0300-9629(97)00079-0.Peer-Reviewed Original ResearchConceptsNa-H exchangeCrypt cellsFluid absorptionLamina propria cellsColonic ion transportNet fluid secretionRat distal colonColonic crypt cellsPresence of myofibroblastsApical membrane vesiclesSecretory processRinger-like solutionDibutyryl cyclic AMPDistal colonCrypt preparationNeurohumoral agonistsAcid loadMorphologic techniquesFluid secretionGradient stimulationAbsorptive processesCyclic AMPIndividual cryptsMyofibroblastsBath solution
1995
Fluid absorption in isolated perfused colonic crypts.
Singh S, Binder H, Boron W, Geibel J. Fluid absorption in isolated perfused colonic crypts. Journal Of Clinical Investigation 1995, 96: 2373-2379. PMID: 7593625, PMCID: PMC185889, DOI: 10.1172/jci118294.Peer-Reviewed Original ResearchConceptsCrypt cellsNM vasoactive intestinal peptideFluid absorptionLarge intestinal functionColonic cryptsVasoactive intestinal peptideLamina propria cellsNet fluid secretionRat distal colonNet fluid absorptionDibutyryl cyclic AMPIntestinal peptideDistal colonIntestinal functionLamina propriaPathophysiological paradigmCrypt preparationMM acetylcholineBasal stateNeurohumoral agonistsFluid secretionCellular elementsEpithelial cellsIntestinal cryptsCryptsChloride-dependent Na-H Exchange A NOVEL MECHANISM OF SODIUM TRANSPORT IN COLONIC CRYPTS*
Rajendran V, Geibel J, Binder H. Chloride-dependent Na-H Exchange A NOVEL MECHANISM OF SODIUM TRANSPORT IN COLONIC CRYPTS*. Journal Of Biological Chemistry 1995, 270: 11051-11054. PMID: 7744735, DOI: 10.1074/jbc.270.19.11051.Peer-Reviewed Original ResearchConceptsNa-H exchangeColonic crypt cellsCrypt cellsAcid loadRat distal colonApical membrane vesiclesNovel transport processRate of intracellularDistal colonMM amilorideSodium transportApical membraneGradient stimulationColonic cryptsAmiloride inhibitionSodium movementNovel mechanismOutward gradientCompelling evidenceCellsSodiumUptakePrior studiesColonRecovery