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The IK1/Kir2.1 channel agonist zacopride prevents and cures acute ischemic arrhythmias in the rat. PLoS One 2017; 12:e0177600. [PMID: 28542320 PMCID: PMC5436763 DOI: 10.1371/journal.pone.0177600] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Accepted: 04/20/2017] [Indexed: 12/13/2022] Open
Abstract
Arrhythmogenesis in acute myocardial infarction (MI) is associated with depolarization of resting membraine potential (RMP) and decrease of inward rectifier potassium current (IK1) in cardiomyocytes. However, clinical anti-arrhythmic agents that primarily act on RMP by enhancing the IK1 channel are not currently available. We hypothesized that zacopride, a selective and moderate agonist of the IK1/Kir2.1 channels, prevents and cures acute ischemic arrhythmias. To test this viewpoint, adult Sprague-Dawley (SD) rats were subjected to MI by ligating the left main coronary artery. The antiarrhythmic effects of zacopride (i.v. infusion) were observed in the settings of pre-treatment (zacopride given 3 min prior to coronary occlusion), post-treatment (zacopride given 3 min after coronary occlusion) and therapeutic treatment (zacopride given 30 s after the onset of the first sustained ventricular tachycardia (VT)/ventricular fibrillation (VF) post MI). In all the three treatment modes, zacopride (15 μg/kg) inhibited MI-induced ventricular tachyarrhythmias, as shown by significant decreases in the premature ventricular contraction (PVC) and the duration and incidence of VT or VF. In Langendorff perfused rat hearts, the antiarrhythmic effect of 1 μmol/L zacopride were reversed by 1 μmol/L BaCl2, a blocker of IK1 channel. Patch clamp results in freshly isolated rat ventricular myocytes indicated that zacopride activated the IK1 channel and thereby reversed hypoxia-induced RMP depolarization and action potential duration (APD) prolongation. In addition, zacopride (1 μmol/L) suppressed hypoxia- or isoproterenol- induced delayed afterdepolarizations (DADs). In Kir2.x transfected Chinese hamster ovary (CHO) cells, zacopride activated the Kir2.1 homomeric channel but not the Kir2.2 or Kir2.3 channels. These results support our hypothesis that moderately enhancing IK1/Kir2.1 currents as by zacopride rescues ischemia- and hypoxia- induced RMP depolarization, and thereby prevents and cures acute ischemic arrhythmias. This study brings a new viewpoint to antiarrhythmic theories and provides a promising target for the treatment of acute ischemic arrhythmias.
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Li MH, Leng TD, Feng XC, Yang T, Simon RP, Xiong ZG. Modulation of Acid-sensing Ion Channel 1a by Intracellular pH and Its Role in Ischemic Stroke. J Biol Chem 2016; 291:18370-83. [PMID: 27402850 DOI: 10.1074/jbc.m115.713636] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2016] [Indexed: 12/24/2022] Open
Abstract
An important contributor to brain ischemia is known to be extracellular acidosis, which activates acid-sensing ion channels (ASICs), a family of proton-gated sodium channels. Lines of evidence suggest that targeting ASICs may lead to novel therapeutic strategies for stroke. Investigations of the role of ASICs in ischemic brain injury have naturally focused on the role of extracellular pH in ASIC activation. By contrast, intracellular pH (pHi) has received little attention. This is a significant gap in our understanding because the ASIC response to extracellular pH is modulated by pHi, and activation of ASICs by extracellular protons is paradoxically enhanced by intracellular alkalosis. Our previous studies show that acidosis-induced cell injury in in vitro models is attenuated by intracellular acidification. However, whether pHi affects ischemic brain injury in vivo is completely unknown. Furthermore, whereas ASICs in native neurons are composed of different subunits characterized by distinct electrophysiological/pharmacological properties, the subunit-dependent modulation of ASIC activity by pHi has not been investigated. Using a combination of in vitro and in vivo ischemic brain injury models, electrophysiological, biochemical, and molecular biological approaches, we show that the intracellular alkalizing agent quinine potentiates, whereas the intracellular acidifying agent propionate inhibits, oxygen-glucose deprivation-induced cell injury in vitro and brain ischemia-induced infarct volume in vivo Moreover, we find that the potentiation of ASICs by quinine depends on the presence of the ASIC1a, ASIC2a subunits, but not ASIC1b, ASIC3 subunits. Furthermore, we have determined the amino acids in ASIC1a that are involved in the modulation of ASICs by pHi.
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Affiliation(s)
- Ming-Hua Li
- From the Department of Neurological Surgery, Oregon Health and Science University, Portland, Oregon 97239,
| | - Tian-Dong Leng
- the Department of Neurobiology, Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia 30310, and
| | - Xue-Chao Feng
- the Key Laboratory of Molecular Epigenetics of Ministry of Education, Institute of Cytology and Genetics, Northeast Normal University, 130000 Changchun, China
| | - Tao Yang
- the Department of Neurobiology, Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia 30310, and
| | - Roger P Simon
- the Department of Neurobiology, Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia 30310, and
| | - Zhi-Gang Xiong
- the Department of Neurobiology, Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia 30310, and
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Zhao J, Li P, Motes CM, Park S, Hirschi KD. CHX14 is a plasma membrane K-efflux transporter that regulates K(+) redistribution in Arabidopsis thaliana. PLANT, CELL & ENVIRONMENT 2015; 38:2223-38. [PMID: 25754420 DOI: 10.1111/pce.12524] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 02/19/2015] [Indexed: 05/22/2023]
Abstract
Potassium (K(+) ) is essential for plant growth and development, yet the molecular identity of many K(+) transporters remains elusive. Here we characterized cation/H(+) exchanger (CHX) 14 as a plasma membrane K(+) transporter. CHX14 expression was induced by elevated K(+) and histochemical analysis of CHX14 promoter::GUS transgenic plants indicated that CHX14 was expressed in xylem parenchyma of root and shoot vascular tissues of seedlings. CHX14 knockout (chx14) and CHX14 overexpression seedlings displayed different growth phenotypes during K(+) stress as compared with wild-type seedlings. Roots of mutant seedlings displayed higher K(+) uptake rates than wild-type roots. CHX14 expression in yeast cells deficient in K(+) uptake renders the mutant cells more sensitive to deficiencies of K(+) in the medium. CHX14 mediates K(+) efflux in yeast cells loaded with high K(+) . Uptake experiments using (86) Rb(+) as a tracer for K(+) with both yeast and plant mutants demonstrated that CHX14 expression in yeast and in planta mediated low-affinity K(+) efflux. Functional green fluorescent protein (GFP)-tagged versions of CHX14 were localized to both the yeast and plant plasma membranes. Taken together, we suggest that CHX14 is a plasma membrane K(+) efflux transporter involved in K(+) homeostasis and K(+) recirculation.
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Affiliation(s)
- Jian Zhao
- National Key Laboratory of Crop Genetic Improvement, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
- Agricultural Research Service Children's Nutrition Research Center, United States Department of Agriculture, Baylor College of Medicine, 1100 Bates Street, Houston, TX, 77030, USA
| | - Penghui Li
- National Key Laboratory of Crop Genetic Improvement, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Christy M Motes
- Plant Biology Division, Samuel Roberts Noble Foundation Inc, 2510 Sam Noble Parkway, Ardmore, OK, 73401, USA
| | - Sunghun Park
- Department of Horticulture, Forestry and Recreation Resources, Kansas State University, Manhattan, KS, 66506, USA
| | - Kendal D Hirschi
- Agricultural Research Service Children's Nutrition Research Center, United States Department of Agriculture, Baylor College of Medicine, 1100 Bates Street, Houston, TX, 77030, USA
- Vegetable and Fruit Improvement Center, Texas A&M University, College Station, TX, 77845, USA
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Alexandre J, Hof T, Puddu PE, Rouet R, Guinamard R, Manrique A, Beygui F, Sallé L, Milliez P. Rapid and MR-Independent IK1 Activation by Aldosterone during Ischemia-Reperfusion. PLoS One 2015. [PMID: 26222262 PMCID: PMC4519293 DOI: 10.1371/journal.pone.0132592] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
In ST elevation myocardial infarction (STEMI) context, clinical studies have shown the deleterious effect of high aldosterone levels on ventricular arrhythmia occurrence and cardiac mortality. Previous in vitro reports showed that during ischemia-reperfusion, aldosterone modulates K+ currents involved in the holding of the resting membrane potential (RMP). The aim of this study was to assess the electrophysiological impact of aldosterone on IK1 current during myocardial ischemia-reperfusion. We used an in vitro model of “border zone” using right rabbit ventricle and standard microelectrode technique followed by cell-attached recordings from freshly isolated rabbit ventricular cardiomyocytes. In microelectrode experiments, aldosterone (10 and 100 nmol/L, n=7 respectively) increased the action potential duration (APD) dispersion at 90% between ischemic and normoxic zones (from 95±4 ms to 116±6 ms and 127±5 ms respectively, P<0.05) and reperfusion-induced sustained premature ventricular contractions occurrence (from 2/12 to 5/7 preparations, P<0.05). Conversely, potassium canrenoate 100 nmol/L and RU 28318 1 μmol/l alone did not affect AP parameters and premature ventricular contractions occurrence (except Vmax which was decreased by potassium canrenoate during simulated-ischemia). Furthermore, aldosterone induced a RMP hyperpolarization, evoking an implication of a K+ current involved in the holding of the RMP. Cell-attached recordings showed that aldosterone 10 nmol/L quickly activated (within 6.2±0.4 min) a 30 pS K+-selective current, inward rectifier, with pharmacological and biophysical properties consistent with the IK1 current (NPo =1.9±0.4 in control vs NPo=3.0±0.4, n=10, P<0.05). These deleterious effects persisted in presence of RU 28318, a specific MR antagonist, and were successfully prevented by potassium canrenoate, a non specific MR antagonist, in both microelectrode and patch-clamp recordings, thus indicating a MR-independent IK1 activation. In this ischemia-reperfusion context, aldosterone induced rapid and MR-independent deleterious effects including an arrhythmia substrate (increased APD90 dispersion) and triggered activities (increased premature ventricular contractions occurrence on reperfusion) possibly related to direct IK1 activation.
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Affiliation(s)
- Joachim Alexandre
- CHU de Caen, Department of Cardiology, Caen, France
- Université de Caen Basse-Normandie, EA 4650 Signalisation, électrophysiologie et imagerie des lésions d'ischémie-reperfusion myocardique, Caen, France
| | - Thomas Hof
- Université de Caen Basse-Normandie, EA 4650 Signalisation, électrophysiologie et imagerie des lésions d'ischémie-reperfusion myocardique, Caen, France
| | | | - René Rouet
- Université de Caen Basse-Normandie, EA 4650 Signalisation, électrophysiologie et imagerie des lésions d'ischémie-reperfusion myocardique, Caen, France
- Université de Caen Basse-Normandie, Medical School, Caen, F-14000, France
| | - Romain Guinamard
- Université de Caen Basse-Normandie, EA 4650 Signalisation, électrophysiologie et imagerie des lésions d'ischémie-reperfusion myocardique, Caen, France
- Université de Caen Basse-Normandie, Medical School, Caen, F-14000, France
| | - Alain Manrique
- Université de Caen Basse-Normandie, EA 4650 Signalisation, électrophysiologie et imagerie des lésions d'ischémie-reperfusion myocardique, Caen, France
- Université de Caen Basse-Normandie, Medical School, Caen, F-14000, France
| | - Farzin Beygui
- CHU de Caen, Department of Cardiology, Caen, France
- Université de Caen Basse-Normandie, Medical School, Caen, F-14000, France
| | - Laurent Sallé
- Université de Caen Basse-Normandie, EA 4650 Signalisation, électrophysiologie et imagerie des lésions d'ischémie-reperfusion myocardique, Caen, France
- Université de Caen Basse-Normandie, Medical School, Caen, F-14000, France
| | - Paul Milliez
- CHU de Caen, Department of Cardiology, Caen, France
- Université de Caen Basse-Normandie, EA 4650 Signalisation, électrophysiologie et imagerie des lésions d'ischémie-reperfusion myocardique, Caen, France
- Université de Caen Basse-Normandie, Medical School, Caen, F-14000, France
- * E-mail:
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Monteith A, Marszalec W, Chan P, Logan J, Yu W, Schwarz N, Wokosin D, Hockberger P. Imaging of mitochondrial and non-mitochondrial responses in cultured rat hippocampal neurons exposed to micromolar concentrations of TMRM. PLoS One 2013; 8:e58059. [PMID: 23483968 PMCID: PMC3587568 DOI: 10.1371/journal.pone.0058059] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Accepted: 01/31/2013] [Indexed: 11/24/2022] Open
Abstract
Tetramethylrhodamine methyl ester (TMRM) is a fluorescent dye used to study mitochondrial function in living cells. Previously, we reported that TMRM effectively labeled mitochondria of neurons deep within mouse brain slices. Use of micromolar concentration of dye, which was required to get sufficient staining for two-photon imaging, resulted in typical fluctuations of TMRM. With prolonged exposure, we recorded additional responses in some neurons that included slow oscillations and propagating waves of fluorescence. (Note: We use the terms “fluctuation” to refer to a change in the fluorescent state of an individual mitochondrion, “oscillation” to refer to a localized change in fluorescence in the cytosol, and “wave” to refer to a change in cytosolic fluorescence that propagated within a cell. Use of these terms does not imply any underlying periodicity.) In this report we describe similar results using cultured rat hippocampal neurons. Prolonged exposure of cultures to 2.5 µM TMRM produced a spontaneous increase in fluorescence in some neurons, but not glial cells, after 45–60 minutes that was followed by slow oscillations, waves, and eventually apoptosis. Spontaneous increases in fluorescence were insensitive to high concentrations of FCCP (100 µM) and thapsigargin (10 µM) indicating that they originated, at least in part, from regions outside of mitochondria. The oscillations did not correlate with changes in intracellular Ca2+, but did correlate with differences in fluorescence lifetime of the dye. Fluorescence lifetime and one-photon ratiometric imaging of TMRM suggested that the spontaneous increase and subsequent oscillations were due to movement of dye between quenched (hydrophobic) and unquenched (hydrophilic) compartments. We propose that these movements may be correlates of intracellular events involved in early stages of apoptosis.
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Affiliation(s)
- Andrew Monteith
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - William Marszalec
- Department of Molecular Pharmacology and Biological Chemistry, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Philip Chan
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Juliette Logan
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Weiming Yu
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Nicholas Schwarz
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - David Wokosin
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Philip Hockberger
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
- * E-mail:
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Goldoni D, Zhao Y, Green BD, McDermott BJ, Collins A. Inward rectifier potassium channels in the HL-1 cardiomyocyte-derived cell line. J Cell Physiol 2010; 225:751-6. [PMID: 20568224 DOI: 10.1002/jcp.22278] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
HL-1 is a line of immortalized cells of cardiomyocyte origin that are a useful complement to native cardiomyocytes in studies of cardiac gene regulation. Several types of ion channel have been identified in these cells, but not the physiologically important inward rectifier K(+) channels. Our aim was to identify and characterize inward rectifier K(+) channels in HL-1 cells. External Ba(2+) (100 µM) inhibited 44 ± 0.05% (mean ± s.e.m., n = 11) of inward current in whole-cell patch-clamp recordings. The reversal potential of the Ba(2+)-sensitive current shifted with external [K(+)] as expected for K(+)-selective channels. The slope conductance of the inward Ba(2+)-sensitive current increased with external [K(+)]. The apparent Kd for Ba(2+) was voltage dependent, ranging from 15 µM at -150 mV to 148 µM at -75 mV in 120 mM external K(+). This current was insensitive to 10 µM glybenclamide. A component of whole-cell current was sensitive to 150 µM 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS), although it did not correspond to the Ba(2+)-sensitive component. The effect of external 1 mM Cs(+) was similar to that of Ba(2+). Polymerase chain reaction using HL-1 cDNA as template and primers specific for the cardiac inward rectifier K(ir)2.1 produced a fragment of the expected size that was confirmed to be K(ir)2.1 by DNA sequencing. In conclusion, HL-1 cells express a current that is characteristic of cardiac inward rectifier K(+) channels, and express K(ir)2.1 mRNA. This cell line may have use as a system for studying inward rectifier gene regulation in a cardiomyocyte phenotype.
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Affiliation(s)
- Dana Goldoni
- Cardiovascular Remodelling Group, Centre for Vision and Vascular Science, School of Medicine, Dentistry and Biomedical Sciences, Queen's University, Belfast, UK
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McDermott JR, Jiang X, Beene LC, Rosen BP, Liu Z. Pentavalent methylated arsenicals are substrates of human AQP9. Biometals 2010; 23:119-27. [PMID: 19802720 PMCID: PMC4266138 DOI: 10.1007/s10534-009-9273-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2009] [Accepted: 09/22/2009] [Indexed: 01/08/2023]
Abstract
Liver aquaglyceroporin AQP9 facilitates movement of trivalent inorganic arsenite (As(III)) and organic monomethylarsonous acid (MAs(III)). However, the transport pathway for the two major pentavalent arsenic cellular metabolites, MAs(V) and DMAs(V), remains unknown in mammals. These products of arsenic metabolism, in particular DMAs(V), are the major arsenicals excreted in the urine of mammals. In this study, we examined the uptake of the two pentavalent organic arsenicals by human AQP9 in Xenopus laevis oocytes. Xenopus laevis oocytes microinjected with AQP9 cRNA exhibited uptake of both MAs(V) and DMAs(V) in a pH-dependent manner. The rate of transport was much higher at acidic pH (pH5.5) than at neutral pH. Hg(II), an aquaporin inhibitor, inhibited transport of As(III), MAs(III), MAs(V) and DMAs(V) via AQP9. However, phloretin, which inhibits water and glycerol permeation via AQP9, can only inhibit transport of pentavalent MAs(V) and DMAs(V) but not trivalent As(III) and MAs(III), indicating the translocation mechanisms of these arsenic species are not exactly the same. Reagents such as FCCP, valinomycin and nigericin that dissipate transmembrane proton potential or change the transmemebrane pH gradient did not significantly inhibit all arsenic transport via AQP9, suggesting the transport of pentavalent arsenic is not proton coupled. The results suggest that in addition to the initial uptake of trivalent inorganic As(III) inside cells, AQP9 plays a dual role in the detoxification of arsenic metabolites by facilitating efflux from cells.
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Affiliation(s)
- Joseph R. McDermott
- Department of Biological Sciences, Oakland University, Dodge Hall 325, 2200 N. Squirrel Rd, Rochester, MI 48309, USA
| | - Xuan Jiang
- Departments of Biochemistry and Molecular Biology, School of Medicine, Wayne State University, 540 E. Canfield Ave, Detroit, MI 48201, USA
| | - Lauren C. Beene
- Department of Biological Sciences, Oakland University, Dodge Hall 325, 2200 N. Squirrel Rd, Rochester, MI 48309, USA
| | - Barry P. Rosen
- Departments of Biochemistry and Molecular Biology, School of Medicine, Wayne State University, 540 E. Canfield Ave, Detroit, MI 48201, USA; Florida International University, College of Medicine, 11200 SW 8th Street, HLS II 693, Miami, FL 33199, USA
| | - Zijuan Liu
- Department of Biological Sciences, Oakland University, Dodge Hall 325, 2200 N. Squirrel Rd, Rochester, MI 48309, USA
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Collins A, Wang H, Larson MK. Differential sensitivity of Kir2 inward-rectifier potassium channels to a mitochondrial uncoupler: identification of a regulatory site. Mol Pharmacol 2005; 67:1214-20. [PMID: 15632319 DOI: 10.1124/mol.104.008292] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The aim of this study was to gain insight into the mechanism by which members of the K(ir)2 subfamily are differentially sensitive to agents that inhibit mitochondrial function by identifying responsible site(s) in K(ir)2 proteins. K(ir)2 channels were expressed in Xenopus laevis oocytes and assayed by two-electrode voltage clamp and patch clamp. Incubation of oocytes in carbonyl cyanide p-trifluoromethoxyphenylhydrazone (FCCP), a mitochondrial uncoupler, inhibited K(ir)2.2 and K(ir)2.3, but not K(ir)2.1. Replacement of the first 44 amino acids of K(ir)2.2 the or of first 19 K(ir)2.3 with the first 45 of K(ir)2.1 did not affect the sensitivity of the channels to FCCP. In contrast, a larger substitution of K(ir)2.1 N-terminal sequence (1-78) into K(ir)2.2 or K(ir)2.3 produced channels that were resistant to FCCP. Sequence alignment between residues 46 and 78 (K(ir)2.1 numbering) revealed four residues that are the same in K(ir)2.2 and K(ir)2.3 but different in K(ir)2.1. Each of these four residues in the resistant chimera was converted back to the K(ir)2.2/K(ir)2.3 amino acid. Three of the mutants (D51N, I59A, and G65S) were not sensitive to FCCP, but the H53Q mutant was sensitive. K(ir)2.1-H53A and K(ir)2.1-H53E were also sensitive. In contrast, K(ir)2.1-H53R and K(ir)2.1-H53K were recovered during resistant. K(ir)2.2 and K(ir)2.3 currents perfusion of inside-out patches from FCCP-treated oocytes. FCCP was without effect on K(ir)2.2 and K(ir)2.3 when applied directly to inside-out patches. Together, these results suggest inhibition of K(ir)2.2 and K(ir)2.3 by a ligand that bears a positive charge and is produced by an intracellular action of FCCP.
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Affiliation(s)
- Anthony Collins
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, OR 97331-3507, USA.
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