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Thapliyal S, Arendt KL, Lau AG, Chen L. Correction: Retinoic acid-gated BDNF synthesis in neuronal dendrites drives presynaptic homeostatic plasticity. eLife 2023; 12:e91539. [PMID: 37530757 PMCID: PMC10396336 DOI: 10.7554/elife.91539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/03/2023] Open
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Thapliyal S, Arendt KL, Lau AG, Chen L. Retinoic acid-gated BDNF synthesis in neuronal dendrites drives presynaptic homeostatic plasticity. eLife 2022; 11:79863. [PMID: 36515276 PMCID: PMC9797192 DOI: 10.7554/elife.79863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 11/23/2022] [Indexed: 12/15/2022] Open
Abstract
Homeostatic synaptic plasticity is a non-Hebbian synaptic mechanism that adjusts synaptic strength to maintain network stability while achieving optimal information processing. Among the molecular mediators shown to regulate this form of plasticity, synaptic signaling through retinoic acid (RA) and its receptor, RARα, has been shown to be critically involved in the homeostatic adjustment of synaptic transmission in both hippocampus and sensory cortices. In this study, we explore the molecular mechanism through which postsynaptic RA and RARα regulates presynaptic neurotransmitter release during prolonged synaptic inactivity at mouse glutamatertic synapses. We show that RARα binds to a subset of dendritically sorted brain-derived neurotrophic factor (Bdnf) mRNA splice isoforms and represses their translation. The RA-mediated translational de-repression of postsynaptic BDNF results in the retrograde activation of presynaptic tropomyosin receptor kinase B (TrkB) receptors, facilitating presynaptic homeostatic compensation through enhanced presynaptic release. Together, our study illustrates an RA-mediated retrograde synaptic signaling pathway through which postsynaptic protein synthesis during synaptic inactivity drives compensatory changes at the presynaptic site.
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Affiliation(s)
- Shruti Thapliyal
- Departments of Neurosurgery, Neuropsychiatry and Behavioral Sciences, Stanford University School of MedicineStanfordUnited States
| | - Kristin L Arendt
- Departments of Neurosurgery, Neuropsychiatry and Behavioral Sciences, Stanford University School of MedicineStanfordUnited States
| | - Anthony G Lau
- Departments of Neurosurgery, Neuropsychiatry and Behavioral Sciences, Stanford University School of MedicineStanfordUnited States
| | - Lu Chen
- Departments of Neurosurgery, Neuropsychiatry and Behavioral Sciences, Stanford University School of MedicineStanfordUnited States
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3
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Park E, Lau AG, Arendt KL, Chen L. FMRP Interacts with RARα in Synaptic Retinoic Acid Signaling and Homeostatic Synaptic Plasticity. Int J Mol Sci 2021; 22:ijms22126579. [PMID: 34205274 PMCID: PMC8235556 DOI: 10.3390/ijms22126579] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 06/16/2021] [Accepted: 06/17/2021] [Indexed: 01/08/2023] Open
Abstract
The fragile X syndrome (FXS) is an X-chromosome-linked neurodevelopmental disorder with severe intellectual disability caused by inactivation of the fragile X mental retardation 1 (FMR1) gene and subsequent loss of the fragile X mental retardation protein (FMRP). Among the various types of abnormal synaptic function and synaptic plasticity phenotypes reported in FXS animal models, defective synaptic retinoic acid (RA) signaling and subsequent defective homeostatic plasticity have emerged as a major synaptic dysfunction. However, the mechanism underlying the defective synaptic RA signaling in the absence of FMRP is unknown. Here, we show that RARα, the RA receptor critically involved in synaptic RA signaling, directly interacts with FMRP. This interaction is enhanced in the presence of RA. Blocking the interaction between FMRP and RARα with a small peptide corresponding to the critical binding site in RARα abolishes RA-induced increases in excitatory synaptic transmission, recapitulating the phenotype seen in the Fmr1 knockout mouse. Taken together, these data suggest that not only are functional FMRP and RARα necessary for RA-dependent homeostatic synaptic plasticity, but that the interaction between these two proteins is essential for proper transcription-independent RA signaling. Our results may provide further mechanistic understanding into FXS synaptic pathophysiology.
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Li J, Jiang RY, Arendt KL, Hsu YT, Zhai SR, Chen L. Defective memory engram reactivation underlies impaired fear memory recall in Fragile X syndrome. eLife 2020; 9:61882. [PMID: 33215988 PMCID: PMC7679137 DOI: 10.7554/elife.61882] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 11/13/2020] [Indexed: 11/25/2022] Open
Abstract
Fragile X syndrome (FXS) is an X chromosome-linked disease associated with severe intellectual disabilities. Previous studies using the Fmr1 knockout (KO) mouse, an FXS mouse model, have attributed behavioral deficits to synaptic dysfunctions. However, how functional deficits at neural network level lead to abnormal behavioral learning remains unexplored. Here, we show that the efficacy of hippocampal engram reactivation is reduced in Fmr1 KO mice performing contextual fear memory recall. Experiencing an enriched environment (EE) prior to learning improved the engram reactivation efficacy and rescued memory recall in the Fmr1 KO mice. In addition, chemogenetically inhibiting EE-engaged neurons in CA1 reverses the rescue effect of EE on memory recall. Thus, our results suggest that inappropriate engram reactivation underlies cognitive deficits in FXS, and enriched environment may rescue cognitive deficits by improving network activation accuracy.
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Affiliation(s)
- Jie Li
- Department of Neurosurgery, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, United States
| | - Rena Y Jiang
- Department of Neurosurgery, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, United States
| | - Kristin L Arendt
- Department of Neurosurgery, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, United States
| | - Yu-Tien Hsu
- Department of Neurosurgery, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, United States
| | - Sophia R Zhai
- Department of Neurosurgery, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, United States
| | - Lu Chen
- Department of Neurosurgery, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, United States
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Zhang Z, Marro SG, Zhang Y, Arendt KL, Patzke C, Zhou B, Fair T, Yang N, Südhof TC, Wernig M, Chen L. The fragile X mutation impairs homeostatic plasticity in human neurons by blocking synaptic retinoic acid signaling. Sci Transl Med 2018; 10:eaar4338. [PMID: 30068571 PMCID: PMC6317709 DOI: 10.1126/scitranslmed.aar4338] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 07/12/2018] [Indexed: 11/02/2022]
Abstract
Fragile X syndrome (FXS) is an X chromosome-linked disease leading to severe intellectual disabilities. FXS is caused by inactivation of the fragile X mental retardation 1 (FMR1) gene, but how FMR1 inactivation induces FXS remains unclear. Using human neurons generated from control and FXS patient-derived induced pluripotent stem (iPS) cells or from embryonic stem cells carrying conditional FMR1 mutations, we show here that loss of FMR1 function specifically abolished homeostatic synaptic plasticity without affecting basal synaptic transmission. We demonstrated that, in human neurons, homeostatic plasticity induced by synaptic silencing was mediated by retinoic acid, which regulated both excitatory and inhibitory synaptic strength. FMR1 inactivation impaired homeostatic plasticity by blocking retinoic acid-mediated regulation of synaptic strength. Repairing the genetic mutation in the FMR1 gene in an FXS patient cell line restored fragile X mental retardation protein (FMRP) expression and fully rescued synaptic retinoic acid signaling. Thus, our study reveals a robust functional impairment caused by FMR1 mutations that might contribute to neuronal dysfunction in FXS. In addition, our results suggest that FXS patient iPS cell-derived neurons might be useful for studying the mechanisms mediating functional abnormalities in FXS.
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Affiliation(s)
- Zhenjie Zhang
- Departments of Neurosurgery, and Psychiatry and Behavioral Sciences, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305-5453, USA
| | - Samuele G Marro
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305-5453, USA
- Institute of Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305-5453, USA
| | - Yingsha Zhang
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305-5453, USA
| | - Kristin L Arendt
- Departments of Neurosurgery, and Psychiatry and Behavioral Sciences, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305-5453, USA
| | - Christopher Patzke
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305-5453, USA
| | - Bo Zhou
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305-5453, USA
| | - Tyler Fair
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305-5453, USA
- Institute of Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305-5453, USA
| | - Nan Yang
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305-5453, USA
- Institute of Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305-5453, USA
| | - Thomas C Südhof
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305-5453, USA.
- Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA 94305-5453, USA
| | - Marius Wernig
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305-5453, USA.
- Institute of Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305-5453, USA
| | - Lu Chen
- Departments of Neurosurgery, and Psychiatry and Behavioral Sciences, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305-5453, USA.
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Wu D, Bacaj T, Morishita W, Goswami D, Arendt KL, Xu W, Chen L, Malenka RC, Südhof TC. Postsynaptic synaptotagmins mediate AMPA receptor exocytosis during LTP. Nature 2017; 544:316-321. [PMID: 28355182 PMCID: PMC5734942 DOI: 10.1038/nature21720] [Citation(s) in RCA: 127] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 02/22/2017] [Indexed: 12/19/2022]
Abstract
Strengthening of synaptic connections by NMDA-receptor-dependent long-term potentiation (LTP) shapes neural circuits and mediates learning and memory. During NMDA-receptor-dependent LTP induction, Ca2+-influx stimulates recruitment of synaptic AMPA-receptors, thereby strengthening synapses. How Ca2+ induces AMPA-receptor recruitment, however, remains unclear. Here we show that, in pyramidal neurons of the hippocampal CA1-region, blocking postsynaptic expression of both synaptotagmin-1 and synaptotagmin-7, but not of synaptotagmin-1 or synaptotagmin-7 alone, abolished LTP. LTP was rescued by wild-type but not by Ca2+-binding-deficient mutant synaptotagmin-7. Blocking postsynaptic synaptotagmin-1/7 expression did not impair basal synaptic transmission, synaptic or extrasynaptic AMPA-receptor levels, or other AMPA-receptor trafficking events. Moreover, expression of dominant-negative mutant synaptotagmin-1 that inhibited Ca2+-dependent presynaptic vesicle exocytosis also blocked Ca2+-dependent postsynaptic AMPA-receptor exocytosis, thereby abolishing LTP. Our results suggest that postsynaptic synaptotagmin-1 and synaptotagmin-7 act as redundant Ca2+-sensors for Ca2+-dependent exocytosis of AMPA-receptors during LTP, thus delineating a simple mechanism for the recruitment of AMPA-receptors that mediates LTP.
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Affiliation(s)
- Dick Wu
- Department of Molecular &Cellular Physiology and Howard Hughes Medical Institute, Stanford University Medical School, Stanford, California 94305, USA.,Nancy Pritzker Laboratory, Stanford University Medical School, Stanford, California 94305, USA.,Department of Psychiatry &Behavioral Sciences, Stanford University Medical School, Stanford, California 94305, USA
| | - Taulant Bacaj
- Department of Molecular &Cellular Physiology and Howard Hughes Medical Institute, Stanford University Medical School, Stanford, California 94305, USA
| | - Wade Morishita
- Nancy Pritzker Laboratory, Stanford University Medical School, Stanford, California 94305, USA.,Department of Psychiatry &Behavioral Sciences, Stanford University Medical School, Stanford, California 94305, USA
| | - Debanjan Goswami
- Nancy Pritzker Laboratory, Stanford University Medical School, Stanford, California 94305, USA.,Department of Psychiatry &Behavioral Sciences, Stanford University Medical School, Stanford, California 94305, USA
| | - Kristin L Arendt
- Department of Neurosurgery, Stanford University Medical School, Stanford, California 94305, USA
| | - Wei Xu
- Department of Molecular &Cellular Physiology and Howard Hughes Medical Institute, Stanford University Medical School, Stanford, California 94305, USA
| | - Lu Chen
- Department of Neurosurgery, Stanford University Medical School, Stanford, California 94305, USA
| | - Robert C Malenka
- Nancy Pritzker Laboratory, Stanford University Medical School, Stanford, California 94305, USA.,Department of Psychiatry &Behavioral Sciences, Stanford University Medical School, Stanford, California 94305, USA
| | - Thomas C Südhof
- Department of Molecular &Cellular Physiology and Howard Hughes Medical Institute, Stanford University Medical School, Stanford, California 94305, USA
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Arendt KL, Zhang Y, Jurado S, Malenka RC, Südhof TC, Chen L. Retinoic Acid and LTP Recruit Postsynaptic AMPA Receptors Using Distinct SNARE-Dependent Mechanisms. Neuron 2015; 86:442-56. [PMID: 25843403 DOI: 10.1016/j.neuron.2015.03.009] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 02/06/2015] [Accepted: 02/26/2015] [Indexed: 11/28/2022]
Abstract
Retinoic acid (RA)-dependent homeostatic plasticity and NMDA receptor-dependent long-term potentiation (LTP), a form of Hebbian plasticity, both enhance synaptic strength by increasing the abundance of postsynaptic AMPA receptors (AMPARs). However, it is unclear whether the molecular mechanisms mediating AMPAR trafficking during homeostatic and Hebbian plasticity differ, and it is unknown how RA signaling impacts Hebbian plasticity. Here, we show that RA increases postsynaptic AMPAR abundance using an activity-dependent mechanism that requires a unique SNARE (soluble NSF-attachment protein receptor)-dependent fusion machinery different from that mediating LTP. Specifically, RA-induced AMPAR trafficking did not involve complexin, which activates SNARE complexes containing syntaxin-1 or -3, but not complexes containing syntaxin-4, whereas LTP required complexin. Moreover, RA-induced AMPAR trafficking utilized the Q-SNARE syntaxin-4, whereas LTP utilized syntaxin-3; both additionally required the Q-SNARE SNAP-47 and the R-SNARE synatobrevin-2. Finally, acute RA treatment blocked subsequent LTP expression, probably by increasing AMPAR trafficking. Thus, RA-induced homeostatic plasticity involves a novel, activity-dependent postsynaptic AMPAR-trafficking pathway mediated by a unique SNARE-dependent fusion machinery.
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Affiliation(s)
- Kristin L Arendt
- Department of Neurosurgery, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305-5453, USA
| | - Yingsha Zhang
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305-5453, USA
| | - Sandra Jurado
- Nancy Pritzker Laboratory, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305-5453, USA
| | - Robert C Malenka
- Nancy Pritzker Laboratory, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305-5453, USA
| | - Thomas C Südhof
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305-5453, USA; Howard Hughes Medical Institute, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305-5453, USA
| | - Lu Chen
- Department of Neurosurgery, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305-5453, USA.
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Arendt KL, Benoist M, Lario A, Draffin JE, Muñoz M, Esteban JA. PTEN counteracts PIP3 upregulation in spines during NMDA-receptor-dependent long-term depression. J Cell Sci 2014; 127:5253-60. [PMID: 25335889 DOI: 10.1242/jcs.156554] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Phosphoinositide 3-kinase (PI3K) and PTEN have been shown to participate in synaptic plasticity during long-term potentiation (LTP) and long-term depression (LTD), respectively. Nevertheless, the dynamics of phosphatidylinositol-(3,4,5)-trisphosphate (PIP3) and the regulation of its synthesis and degradation at synaptic compartments is far from clear. Here, we have used fluorescence resonance energy transfer (FRET) imaging to monitor changes in PIP3 levels in dendritic spines from CA1 hippocampal neurons under basal conditions and upon induction of NMDA receptor (NMDAR)-dependent LTD and LTP. We found that PIP3 undergoes constant turnover in dendritic spines. Contrary to expectations, both LTD and LTP induction trigger an increase in PIP3 synthesis, which requires NMDARs and PI3K activity. Using biochemical methods, the upregulation of PIP3 levels during LTP was estimated to be twofold. However, in the case of LTD, PTEN activity counteracts the increase in PIP3 synthesis, resulting in no net change in PIP3 levels. Therefore, both LTP and LTD signaling converge towards PIP3 upregulation, but PTEN acts as an LTD-selective switch that determines the outcome of PIP3 accumulation.
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Affiliation(s)
- Kristin L Arendt
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, Michigan 48109, USA
| | - Marion Benoist
- Centro de Biología Molecular "Severo Ochoa", Consejo Superior de Investigaciones Científicas (CSIC)/Universidad Autónoma de Madrid (UAM), Madrid 28049, Spain
| | - Argentina Lario
- Centro de Biología Molecular "Severo Ochoa", Consejo Superior de Investigaciones Científicas (CSIC)/Universidad Autónoma de Madrid (UAM), Madrid 28049, Spain
| | - Jonathan E Draffin
- Centro de Biología Molecular "Severo Ochoa", Consejo Superior de Investigaciones Científicas (CSIC)/Universidad Autónoma de Madrid (UAM), Madrid 28049, Spain
| | - María Muñoz
- Centro de Biología Molecular "Severo Ochoa", Consejo Superior de Investigaciones Científicas (CSIC)/Universidad Autónoma de Madrid (UAM), Madrid 28049, Spain
| | - José A Esteban
- Centro de Biología Molecular "Severo Ochoa", Consejo Superior de Investigaciones Científicas (CSIC)/Universidad Autónoma de Madrid (UAM), Madrid 28049, Spain
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Arendt KL, Royo M, Fernández-Monreal M, Knafo S, Petrok CN, Martens JR, Esteban JA. PIP3 controls synaptic function by maintaining AMPA receptor clustering at the postsynaptic membrane. Nat Neurosci 2009; 13:36-44. [PMID: 20010819 PMCID: PMC2810846 DOI: 10.1038/nn.2462] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2009] [Accepted: 11/04/2009] [Indexed: 12/05/2022]
Abstract
Despite their low abundance, phosphoinositides are critical regulators of intracellular signaling and membrane compartmentalization. However, little is known of phosphoinositide function at the postsynaptic membrane. Here we show that continuous synthesis and availability of phosphatidylinositol-(3,4,5)-trisphosphate (PIP3) at the postsynaptic terminal is necessary for sustaining synaptic function in rat hippocampal neurons. This requirement is specific for synaptic, but not for extrasynaptic, AMPA receptors, nor NMDA receptors. We found that PIP3 down-regulation impairs PSD-95 accumulation in spines. Concomitantly, AMPA receptors become more mobile and migrate from the postsynaptic density towards the perisynaptic membrane within the spine, leading to synaptic depression. Interestingly, these effects are only revealed after prolonged inhibition of PIP3 synthesis or by direct quenching of this phosphoinositide at the postsynaptic cell. Therefore, we conclude that a slow, but constant turnover of PIP3 at synapses is required for maintaining AMPA receptor clustering and synaptic strength under basal conditions.
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Affiliation(s)
- Kristin L Arendt
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, Michigan, USA
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Abstract
Conventional antiarrhythmic drugs target the ion permeability of channels, but increasing evidence suggests that functional ion channel density can also be modified pharmacologically. Kv1.5 mediates the ultrarapid potassium current (I(Kur)) that controls atrial action potential duration. Given the atrial-specific expression of Kv1.5 and its alterations in human atrial fibrillation, significant effort has been made to identify novel channel blockers. In this study, treatment of HL-1 atrial myocytes expressing Kv1.5-GFP with the class I antiarrhythmic agent quinidine resulted in a dose- and temperature-dependent internalization of Kv1.5, concomitant with channel block. This quinidine-induced channel internalization was confirmed in acutely dissociated neonatal myocytes. Channel internalization was subunit-dependent, activity-independent, stereospecific, and blocked by pharmacological disruption of the endocytic machinery. Pore block and channel internalization partially overlap in the structural requirements for drug binding. Surprisingly, quinidine-induced endocytosis was calcium-dependent and therefore unrecognized by previous biophysical studies focused on isolating channel-drug interactions. Importantly, whereas acute quinidine-induced internalization was reversible, chronic treatment led to channel degradation. Together, these data reveal a novel mechanism of antiarrhythmic drug action and highlight the possibility for new agents that selectively modulate the stability of channel protein in the membrane as an approach for treating cardiac arrhythmias.
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Affiliation(s)
- Sarah M Schumacher
- Department of Pharmacology, 1301 MSRBIII, 1150 W Medical Center Dr, Ann Arbor, MI 48109-0632, USA
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Schumacher SM, McEwen DP, Zhang L, Arendt KL, Van Genderen KM, Martens JR. Antiarrhythmic drug‐induced internalization of the atrial specific K+ channel, Kv1.5. FASEB J 2009. [DOI: 10.1096/fasebj.23.1_supplement.579.4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Dyke P McEwen
- Department of PharmacologyUniversity of MichiganAnn ArborMI
| | - Lian Zhang
- Department of PharmacologyUniversity of MichiganAnn ArborMI
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