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Gancayco CA, Gerding MR, Breault DT, Beenhakker MP, Barrett PQ, Guagliardo NA. Intrinsic Adrenal TWIK-Related Acid-Sensitive TASK Channel Dysfunction Produces Spontaneous Calcium Oscillations Sufficient to Drive AngII (Angiotensin II)-Unresponsive Hyperaldosteronism. Hypertension 2022; 79:2552-2564. [PMID: 36129175 PMCID: PMC10167771 DOI: 10.1161/hypertensionaha.122.19557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background:
Ion channel mutations in calcium regulating genes strongly associate with AngII (angiotensin II)-independent aldosterone production. Here, we used an established mouse model of in vivo aldosterone autonomy,
Cyp11b2
-driven deletion of TWIK-related acid-sensitive potassium channels (TASK-1 and TASK-3, termed zona glomerulosa [zG]-TASK-loss-of-function), and selective pharmacological TASK channel inhibition to determine whether channel dysfunction in native, electrically excitable zG cell rosette-assemblies: (1) produces spontaneous calcium oscillatory activity and (2) is sufficient to drive substantial aldosterone autonomy.
Methods:
We imaged calcium activity in adrenal slices expressing a zG-specific calcium reporter (GCaMP3), an in vitro experimental approach that preserves the native rosette assembly and removes potentially confounding extra-adrenal contributions. In parallel experiments, we measured acute aldosterone production from adrenal slice cultures.
Results:
Absent from untreated WT slices, we find that either adrenal-specific genetic deletion or acute pharmacological TASK channel inhibition produces spontaneous oscillatory bursting behavior and steroidogenic activity (2.4-fold) that are robust, sustained, and equivalent to activities evoked by 3 nM AngII in WT slices. Moreover, spontaneous activity in zG-TASK-loss-of-function slices and inhibitor-evoked activity in WT slices are unresponsive to AngII regulation over a wide range of concentrations (50 pM to 3 µM).
Conclusions:
We provide proof of principle that spontaneous activity of zG cells within classic rosette assemblies evoked solely by a change in an intrinsic, dominant resting-state conductance can be a significant source of AngII-independent aldosterone production from native tissue.
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Affiliation(s)
| | - Molly R. Gerding
- Department of Pharmacology (M.R.G., M.P.B., P.Q.B., N.A.G.), University of Virginia, Charlottesville
| | - David T. Breault
- Division of Endocrinology, Boston Children’s Hospital, MA (D.T.B.)
- Harvard Stem Cell Institute, Cambridge, MA (D.T.B.)
| | - Mark P. Beenhakker
- Department of Pharmacology (M.R.G., M.P.B., P.Q.B., N.A.G.), University of Virginia, Charlottesville
| | - Paula Q. Barrett
- Department of Pharmacology (M.R.G., M.P.B., P.Q.B., N.A.G.), University of Virginia, Charlottesville
| | - Nick A. Guagliardo
- Department of Pharmacology (M.R.G., M.P.B., P.Q.B., N.A.G.), University of Virginia, Charlottesville
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2
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Leng S, Carlone DL, Guagliardo NA, Barrett PQ, Breault DT. Rosette morphology in zona glomerulosa formation and function. Mol Cell Endocrinol 2021; 530:111287. [PMID: 33891993 PMCID: PMC8159910 DOI: 10.1016/j.mce.2021.111287] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 03/29/2021] [Accepted: 04/13/2021] [Indexed: 12/18/2022]
Abstract
How morphology informs function is a fundamental biological question. Here, we review the morphological features of the adrenal zona glomerulosa (zG), highlighting recent cellular and molecular discoveries that govern its formation. The zG consists of glomeruli enwrapped in a Laminin-β1-enriched basement membrane (BM). Within each glomerulus, zG cells are organized as rosettes, a multicellular structure widely used throughout development to mediate epithelial remodeling, but not often found in healthy adult tissues. Rosettes arise by constriction at a common cellular contact point mediated/facilitated by adherens junctions (AJs). In mice, small, dispersed AJs first appear postnatally and enrich along the entire cell-cell contact around 10 days after birth. Subsequently, these AJ-rich contacts contract, allowing rosettes to form. Concurrently, flat sheet-like domains in the nascent zG, undergo invagination and folding, gradually giving rise to the compact round glomeruli that comprise the adult zG. How these structures impact adrenal function is discussed.
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Affiliation(s)
- Sining Leng
- Division of Endocrinology, Boston Children's Hospital, Boston, MA, 02115, USA.
| | - Diana L Carlone
- Division of Endocrinology, Boston Children's Hospital, Boston, MA, 02115, USA.
| | - Nick A Guagliardo
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA, USA.
| | - Paula Q Barrett
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA, USA.
| | - David T Breault
- Division of Endocrinology, Boston Children's Hospital, Boston, MA, 02115, USA.
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3
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Barrett PQ, Guagliardo NA, Bayliss DA. Ion Channel Function and Electrical Excitability in the Zona Glomerulosa: A Network Perspective on Aldosterone Regulation. Annu Rev Physiol 2020; 83:451-475. [PMID: 33176563 DOI: 10.1146/annurev-physiol-030220-113038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [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: 12/20/2022]
Abstract
Aldosterone excess is a pathogenic factor in many hypertensive disorders. The discovery of numerous somatic and germline mutations in ion channels in primary hyperaldosteronism underscores the importance of plasma membrane conductances in determining the activation state of zona glomerulosa (zG) cells. Electrophysiological recordings describe an electrically quiescent behavior for dispersed zG cells. Yet, emerging data indicate that in native rosette structures in situ, zG cells are electrically excitable, generating slow periodic voltage spikes and coordinated bursts of Ca2+ oscillations. We revisit data to understand how a multitude of conductances may underlie voltage/Ca2+ oscillations, recognizing that zG layer self-renewal and cell heterogeneity may complicate this task. We review recent data to understand rosette architecture and apply maxims derived from computational network modeling to understand rosette function. The challenge going forward is to uncover how the rosette orchestrates the behavior of a functional network of conditional oscillators to control zG layer performance and aldosterone secretion.
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Affiliation(s)
- Paula Q Barrett
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia 22908, USA; , ,
| | - Nick A Guagliardo
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia 22908, USA; , ,
| | - Douglas A Bayliss
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia 22908, USA; , ,
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4
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DeLalio LJ, Masati E, Mendu S, Ruddiman CA, Yang Y, Johnstone SR, Milstein JA, Keller TCS, Weaver RB, Guagliardo NA, Best AK, Ravichandran KS, Bayliss DA, Sequeira-Lopez MLS, Sonkusare SN, Shu XH, Desai B, Barrett PQ, Le TH, Gomez RA, Isakson BE. Pannexin 1 channels in renin-expressing cells influence renin secretion and blood pressure homeostasis. Kidney Int 2020; 98:630-644. [PMID: 32446934 PMCID: PMC7483468 DOI: 10.1016/j.kint.2020.04.041] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 03/29/2020] [Accepted: 04/02/2020] [Indexed: 02/07/2023]
Abstract
Kidney function and blood pressure homeostasis are regulated by purinergic signaling mechanisms. These autocrine/paracrine signaling pathways are initiated by the release of cellular ATP, which influences kidney hemodynamics and steady-state renin secretion from juxtaglomerular cells. However, the mechanism responsible for ATP release that supports tonic inputs to juxtaglomerular cells and regulates renin secretion remains unclear. Pannexin 1 (Panx1) channels localize to both afferent arterioles and juxtaglomerular cells and provide a transmembrane conduit for ATP release and ion permeability in the kidney and the vasculature. We hypothesized that Panx1 channels in renin-expressing cells regulate renin secretion in vivo. Using a renin cell-specific Panx1 knockout model, we found that male Panx1 deficient mice exhibiting a heightened activation of the renin-angiotensin-aldosterone system have markedly increased plasma renin and aldosterone concentrations, and elevated mean arterial pressure with altered peripheral hemodynamics. Following ovariectomy, female mice mirrored the male phenotype. Furthermore, constitutive Panx1 channel activity was observed in As4.1 renin-secreting cells, whereby Panx1 knockdown reduced extracellular ATP accumulation, lowered basal intracellular calcium concentrations and recapitulated a hyper-secretory renin phenotype. Moreover, in response to stress stimuli that lower blood pressure, Panx1-deficient mice exhibited aberrant "renin recruitment" as evidenced by reactivation of renin expression in pre-glomerular arteriolar smooth muscle cells. Thus, renin-cell Panx1 channels suppress renin secretion and influence adaptive renin responses when blood pressure homeostasis is threatened.
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Affiliation(s)
- Leon J DeLalio
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA; Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Ester Masati
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Suresh Mendu
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Claire A Ruddiman
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA; Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Yang Yang
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA; Department of Pharmacology, Dalian Medical University, Dalian, China
| | - Scott R Johnstone
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Jenna A Milstein
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - T C Stevenson Keller
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA; Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Rachel B Weaver
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Nick A Guagliardo
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Angela K Best
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Kodi S Ravichandran
- Department of Microbiology, Immunology, and Cancer, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Douglas A Bayliss
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Maria Luisa S Sequeira-Lopez
- Pediatric Center of Excellence in Nephrology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Swapnil N Sonkusare
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA; Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Xiaohong H Shu
- Department of Pharmacology, Dalian Medical University, Dalian, China
| | - Bimal Desai
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Paula Q Barrett
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Thu H Le
- Department of Medicine, Division of Nephrology, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
| | - R Ariel Gomez
- Pediatric Center of Excellence in Nephrology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Brant E Isakson
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA; Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, Virginia, USA.
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5
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Guagliardo NA, Klein PM, Gancayco CA, Lu A, Leng S, Makarem RR, Cho C, Rusin CG, Breault DT, Barrett PQ, Beenhakker MP. Angiotensin II induces coordinated calcium bursts in aldosterone-producing adrenal rosettes. Nat Commun 2020; 11:1679. [PMID: 32245948 PMCID: PMC7125102 DOI: 10.1038/s41467-020-15408-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 02/28/2020] [Indexed: 12/15/2022] Open
Abstract
Aldosterone-producing zona glomerulosa (zG) cells of the adrenal gland arrange in distinct multi-cellular rosettes that provide a structural framework for adrenal cortex morphogenesis and plasticity. Whether this cyto-architecture also plays functional roles in signaling remains unexplored. To determine if structure informs function, we generated mice with zG-specific expression of GCaMP3 and imaged zG cells within their native rosette structure. Here we demonstrate that within the rosette, angiotensin II evokes periodic Cav3-dependent calcium events that form bursts that are stereotypic in form. Our data reveal a critical role for angiotensin II in regulating burst occurrence, and a multifunctional role for the rosette structure in activity-prolongation and coordination. Combined our data define the calcium burst as the fundamental unit of zG layer activity evoked by angiotensin II and highlight a novel role for the rosette as a facilitator of cell communication.
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Affiliation(s)
| | - Peter M Klein
- Departments of Pharmacology, Charlottesville, VA, USA
- Neuroscience Graduate Program, University of Virginia, Charlottesville, VA, USA
| | | | - Adam Lu
- Departments of Pharmacology, Charlottesville, VA, USA
- Neuroscience Graduate Program, University of Virginia, Charlottesville, VA, USA
| | - Sining Leng
- Division of Endocrinology, Boston Children's Hospital, Boston, MA, USA
| | | | - Chelsea Cho
- Departments of Pharmacology, Charlottesville, VA, USA
| | - Craig G Rusin
- Department of Pediatrics-Cardiology, Baylor College of Medicine, and Harvard Stem Cell Institute, Cambridge, MA, USA
| | - David T Breault
- Division of Endocrinology, Boston Children's Hospital, Boston, MA, USA
| | | | - Mark P Beenhakker
- Departments of Pharmacology, Charlottesville, VA, USA.
- Neuroscience Graduate Program, University of Virginia, Charlottesville, VA, USA.
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6
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Guagliardo NA, Yao J, Stipes EJ, Cechova S, Le TH, Bayliss DA, Breault DT, Barrett PQ. Adrenal Tissue-Specific Deletion of TASK Channels Causes Aldosterone-Driven Angiotensin II-Independent Hypertension. Hypertension 2019; 73:407-414. [PMID: 30580687 PMCID: PMC6326871 DOI: 10.1161/hypertensionaha.118.11962] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [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: 12/12/2022]
Abstract
The renin-angiotensin system tightly controls aldosterone synthesis. Dysregulation is evident in hypertension (primary aldosteronism), low renin, and resistant hypertension) but also can exist in normotension. Whether chronic, mild aldosterone autonomy can elicit hypertension remains untested. Previously, we reported that global genetic deletion of 2 pore-domain TWIK-relative acid-sensitive potassium channels, TASK-1 and TASK-3, from mice produces striking aldosterone excess, low renin, and hypertension. Here, we deleted TASK-1 and TASK-3 channels selectively from zona glomerulosa cells and generated a model of mild aldosterone autonomy with attendant hypertension that is aldosterone-driven and Ang II (angiotensin II)-independent. This study shows that a zona glomerulosa-specific channel defect can produce mild autonomous hyperaldosteronism sufficient to cause chronic blood pressure elevation.
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Affiliation(s)
- Nick A Guagliardo
- From the Department of Pharmacology (N.A.G., J.Y., E.J.S., D.A.B, P.Q.B.), University of Virginia School of Medicine, Charlottesville
| | - Junlan Yao
- From the Department of Pharmacology (N.A.G., J.Y., E.J.S., D.A.B, P.Q.B.), University of Virginia School of Medicine, Charlottesville
| | - Eric J Stipes
- From the Department of Pharmacology (N.A.G., J.Y., E.J.S., D.A.B, P.Q.B.), University of Virginia School of Medicine, Charlottesville
| | - Sylvia Cechova
- Division of Nephrology, Department of Medicine (S.C., T.H.L.), University of Virginia School of Medicine, Charlottesville
| | - Thu H Le
- Division of Nephrology, Department of Medicine (S.C., T.H.L.), University of Virginia School of Medicine, Charlottesville
| | - Douglas A Bayliss
- From the Department of Pharmacology (N.A.G., J.Y., E.J.S., D.A.B, P.Q.B.), University of Virginia School of Medicine, Charlottesville
| | - David T Breault
- Department of Pediatrics/Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, MA (D.T.B.)
| | - Paula Q Barrett
- From the Department of Pharmacology (N.A.G., J.Y., E.J.S., D.A.B, P.Q.B.), University of Virginia School of Medicine, Charlottesville
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7
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Jing M, Zhang P, Wang G, Feng J, Mesik L, Zeng J, Jiang H, Wang S, Looby JC, Guagliardo NA, Langma LW, Lu J, Zuo Y, Talmage DA, Role LW, Barrett PQ, Zhang LI, Luo M, Song Y, Zhu JJ, Li Y. A genetically encoded fluorescent acetylcholine indicator for in vitro and in vivo studies. Nat Biotechnol 2018; 36:726-737. [PMID: 29985477 PMCID: PMC6093211 DOI: 10.1038/nbt.4184] [Citation(s) in RCA: 204] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 04/30/2018] [Indexed: 02/06/2023]
Abstract
The neurotransmitter acetylcholine (ACh) regulates a diverse array of physiological processes throughout the body. Despite its importance, cholinergic transmission in the majority of tissues and organs remains poorly understood owing primarily to the limitations of available ACh-monitoring techniques. We developed a family of ACh sensors (GACh) based on G-protein-coupled receptors that has the sensitivity, specificity, signal-to-noise ratio, kinetics and photostability suitable for monitoring ACh signals in vitro and in vivo. GACh sensors were validated with transfection, viral and/or transgenic expression in a dozen types of neuronal and non-neuronal cells prepared from multiple animal species. In all preparations, GACh sensors selectively responded to exogenous and/or endogenous ACh with robust fluorescence signals that were captured by epifluorescence, confocal, and/or two-photon microscopy. Moreover, analysis of endogenous ACh release revealed firing-pattern-dependent release and restricted volume transmission, resolving two long-standing questions about central cholinergic transmission. Thus, GACh sensors provide a user-friendly, broadly applicable tool for monitoring cholinergic transmission underlying diverse biological processes.
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Affiliation(s)
- Miao Jing
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing 100871,
China
- PKU-IDG/McGovern Institute for Brain Research, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Beijing 100871, China
| | - Peng Zhang
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA 22908
| | - Guangfu Wang
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA 22908
- Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin
150001, China
| | - Jiesi Feng
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing 100871,
China
- PKU-IDG/McGovern Institute for Brain Research, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Beijing 100871, China
| | - Lukas Mesik
- Zilkha Neurogenetic Institute, Department of Physiology & Neuroscience, Keck School of Medicine,
University of Southern California, Los Angeles, CA, 90033
| | - Jianzhi Zeng
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing 100871,
China
- PKU-IDG/McGovern Institute for Brain Research, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Beijing 100871, China
| | - Huoqing Jiang
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing 100871,
China
- PKU-IDG/McGovern Institute for Brain Research, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Beijing 100871, China
| | - Shaohua Wang
- Department of Neurobiology and Behavior, Stony Brook University, Stony Brook, NY 11794
| | - Jess C. Looby
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA 22908
- Undergraduate Class of 2019, University of Virginia College of Arts and Sciences, Charlottesville, VA
22908
| | - Nick A. Guagliardo
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA 22908
| | - Linda W. Langma
- Department of Surgery, University of Virginia School of Medicine, Charlottesville, VA 22908
| | - Ju Lu
- Department of Surgery, University of Virginia School of Medicine, Charlottesville, VA 22908
| | - Yi Zuo
- Department of Molecular, Cell, and Developmental Biology, University of California, Santa Cruz, CA
95064
| | - David A. Talmage
- Department of Neurobiology and Behavior, Stony Brook University, Stony Brook, NY 11794
| | - Lorna W. Role
- Department of Neurobiology and Behavior, Stony Brook University, Stony Brook, NY 11794
| | - Paula Q. Barrett
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA 22908
| | - Li I. Zhang
- Zilkha Neurogenetic Institute, Department of Physiology & Neuroscience, Keck School of Medicine,
University of Southern California, Los Angeles, CA, 90033
| | - Minmin Luo
- School of Life Sciences, Tsinghua University, Beijing 100084, China
- National Institute of Biological Sciences, Beijing 102206, China
| | - Yan Song
- Peking-Tsinghua Center for Life Sciences, Beijing 100871, China
| | - J. Julius Zhu
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA 22908
- School of Medicine, Ningbo University, Ningbo, 315010, China
- Donders Institute for Brain, Cognition and Behavior, Radboud University Nijmegen, 6525 EN, Nijmegen,
Netherlands
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science
and Technology, Wuhan 430030, China
| | - Yulong Li
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing 100871,
China
- PKU-IDG/McGovern Institute for Brain Research, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Beijing 100871, China
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8
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Yao J, McHedlishvili D, McIntire WE, Guagliardo NA, Erisir A, Coburn CA, Santarelli VP, Bayliss DA, Barrett PQ. Functional TASK-3-Like Channels in Mitochondria of Aldosterone-Producing Zona Glomerulosa Cells. Hypertension 2017. [PMID: 28630209 DOI: 10.1161/hypertensionaha.116.08871] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [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: 12/24/2022]
Abstract
Ca2+ drives aldosterone synthesis in the cytosolic and mitochondrial compartments of the adrenal zona glomerulosa cell. Membrane potential across each of these compartments regulates the amplitude of the Ca2+ signal; yet, only plasma membrane ion channels and their role in regulating cell membrane potential have garnered investigative attention as pathological causes of human hyperaldosteronism. Previously, we reported that genetic deletion of TASK-3 channels (tandem pore domain acid-sensitive K+ channels) from mice produces aldosterone excess in the absence of a change in the cell membrane potential of zona glomerulosa cells. Here, we report using yeast 2-hybrid, immunoprecipitation, and electron microscopic analyses that TASK-3 channels are resident in mitochondria, where they regulate mitochondrial morphology, mitochondrial membrane potential, and aldosterone production. This study provides proof of principle that mitochondrial K+ channels, by modulating inner mitochondrial membrane morphology and mitochondrial membrane potential, have the ability to play a pathological role in aldosterone dysregulation in steroidogenic cells.
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Affiliation(s)
- Junlan Yao
- From the Departments of Pharmacology (J.Y., D.M., W.E.M., N.A.G., D.A.B., P.Q.B.) and Psychology (A.E.), University of Virginia School of Medicine, Charlottesville; Silverback Therapeutics, Inc, Seattle, WA (C.A.C.); and Department of Neuroscience, Merck & Co, Inc, West point, PA (V.P.S.)
| | - David McHedlishvili
- From the Departments of Pharmacology (J.Y., D.M., W.E.M., N.A.G., D.A.B., P.Q.B.) and Psychology (A.E.), University of Virginia School of Medicine, Charlottesville; Silverback Therapeutics, Inc, Seattle, WA (C.A.C.); and Department of Neuroscience, Merck & Co, Inc, West point, PA (V.P.S.)
| | - William E McIntire
- From the Departments of Pharmacology (J.Y., D.M., W.E.M., N.A.G., D.A.B., P.Q.B.) and Psychology (A.E.), University of Virginia School of Medicine, Charlottesville; Silverback Therapeutics, Inc, Seattle, WA (C.A.C.); and Department of Neuroscience, Merck & Co, Inc, West point, PA (V.P.S.)
| | - Nick A Guagliardo
- From the Departments of Pharmacology (J.Y., D.M., W.E.M., N.A.G., D.A.B., P.Q.B.) and Psychology (A.E.), University of Virginia School of Medicine, Charlottesville; Silverback Therapeutics, Inc, Seattle, WA (C.A.C.); and Department of Neuroscience, Merck & Co, Inc, West point, PA (V.P.S.)
| | - Alev Erisir
- From the Departments of Pharmacology (J.Y., D.M., W.E.M., N.A.G., D.A.B., P.Q.B.) and Psychology (A.E.), University of Virginia School of Medicine, Charlottesville; Silverback Therapeutics, Inc, Seattle, WA (C.A.C.); and Department of Neuroscience, Merck & Co, Inc, West point, PA (V.P.S.)
| | - Craig A Coburn
- From the Departments of Pharmacology (J.Y., D.M., W.E.M., N.A.G., D.A.B., P.Q.B.) and Psychology (A.E.), University of Virginia School of Medicine, Charlottesville; Silverback Therapeutics, Inc, Seattle, WA (C.A.C.); and Department of Neuroscience, Merck & Co, Inc, West point, PA (V.P.S.)
| | - Vincent P Santarelli
- From the Departments of Pharmacology (J.Y., D.M., W.E.M., N.A.G., D.A.B., P.Q.B.) and Psychology (A.E.), University of Virginia School of Medicine, Charlottesville; Silverback Therapeutics, Inc, Seattle, WA (C.A.C.); and Department of Neuroscience, Merck & Co, Inc, West point, PA (V.P.S.)
| | - Douglas A Bayliss
- From the Departments of Pharmacology (J.Y., D.M., W.E.M., N.A.G., D.A.B., P.Q.B.) and Psychology (A.E.), University of Virginia School of Medicine, Charlottesville; Silverback Therapeutics, Inc, Seattle, WA (C.A.C.); and Department of Neuroscience, Merck & Co, Inc, West point, PA (V.P.S.)
| | - Paula Q Barrett
- From the Departments of Pharmacology (J.Y., D.M., W.E.M., N.A.G., D.A.B., P.Q.B.) and Psychology (A.E.), University of Virginia School of Medicine, Charlottesville; Silverback Therapeutics, Inc, Seattle, WA (C.A.C.); and Department of Neuroscience, Merck & Co, Inc, West point, PA (V.P.S.).
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9
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Manichaikul A, Rich SS, Allison MA, Guagliardo NA, Bayliss DA, Carey RM, Barrett PQ. KCNK3 Variants Are Associated With Hyperaldosteronism and Hypertension. Hypertension 2016; 68:356-64. [PMID: 27296998 DOI: 10.1161/hypertensionaha.116.07564] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 05/11/2016] [Indexed: 12/19/2022]
Abstract
Blood pressure (BP) is a complex trait that is the consequence of an interaction between genetic and environmental determinants. Previous studies have demonstrated increased BP in mice with global deletion of TASK-1 channels contemporaneous with diverse dysregulation of aldosterone production. In humans, genome-wide association studies in ≈100 000 individuals of European, East Asian, and South Asian ancestry identified a single nucleotide polymorphism (SNP) in KCNK3 (the gene encoding TASK-1) associated with mean arterial pressure. The current study was motivated by the hypotheses that (1) association of KCNK3 SNPs with BP and related traits extends to blacks and Hispanics, and (2) KCNK3 SNPs exhibit associations with plasma renin activity and aldosterone levels. We examined baseline BP measurements for 7840 participants from the Multi-Ethnic Study of Atherosclerosis (MESA), and aldosterone levels and plasma renin activity in a subset of 1653 MESA participants. We identified statistically significant association of the previously reported KCNK3 SNP (rs1275988) with mean arterial pressure in MESA blacks (P=0.024) and a nearby SNP (rs13394970) in MESA Hispanics (P=0.031). We discovered additional KCNK3 SNP associations with systolic BP, mean arterial pressure, and hypertension. We also identified statistically significant association of KCNK3 rs2586886 with plasma aldosterone level in MESA and demonstrated that global deletion of TASK-1 channels in mice produces a mild-hyperaldosteronism, not associated with a decrease in renin. Our results suggest that genetic variation in the KCNK3 gene may contribute to BP variation and less severe hypertensive disorders in which aldosterone may be one of several causative factors.
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Affiliation(s)
- Ani Manichaikul
- From the Center for Public Health Genomics (A.M., S.S.R.), Biostatistics Section, Department of Public Health Sciences (A.M.), Department of Pharmacology (N.A.G., D.A.B., P.Q.B.), and Division of Endocrinology and Metabolism and Department of Medicine (R.M.C.), University of Virginia, Charlottesville; and Department of Family and Preventive Medicine, University of California San Diego, La Jolla (M.A.A.)
| | - Stephen S Rich
- From the Center for Public Health Genomics (A.M., S.S.R.), Biostatistics Section, Department of Public Health Sciences (A.M.), Department of Pharmacology (N.A.G., D.A.B., P.Q.B.), and Division of Endocrinology and Metabolism and Department of Medicine (R.M.C.), University of Virginia, Charlottesville; and Department of Family and Preventive Medicine, University of California San Diego, La Jolla (M.A.A.)
| | - Matthew A Allison
- From the Center for Public Health Genomics (A.M., S.S.R.), Biostatistics Section, Department of Public Health Sciences (A.M.), Department of Pharmacology (N.A.G., D.A.B., P.Q.B.), and Division of Endocrinology and Metabolism and Department of Medicine (R.M.C.), University of Virginia, Charlottesville; and Department of Family and Preventive Medicine, University of California San Diego, La Jolla (M.A.A.)
| | - Nick A Guagliardo
- From the Center for Public Health Genomics (A.M., S.S.R.), Biostatistics Section, Department of Public Health Sciences (A.M.), Department of Pharmacology (N.A.G., D.A.B., P.Q.B.), and Division of Endocrinology and Metabolism and Department of Medicine (R.M.C.), University of Virginia, Charlottesville; and Department of Family and Preventive Medicine, University of California San Diego, La Jolla (M.A.A.)
| | - Douglas A Bayliss
- From the Center for Public Health Genomics (A.M., S.S.R.), Biostatistics Section, Department of Public Health Sciences (A.M.), Department of Pharmacology (N.A.G., D.A.B., P.Q.B.), and Division of Endocrinology and Metabolism and Department of Medicine (R.M.C.), University of Virginia, Charlottesville; and Department of Family and Preventive Medicine, University of California San Diego, La Jolla (M.A.A.)
| | - Robert M Carey
- From the Center for Public Health Genomics (A.M., S.S.R.), Biostatistics Section, Department of Public Health Sciences (A.M.), Department of Pharmacology (N.A.G., D.A.B., P.Q.B.), and Division of Endocrinology and Metabolism and Department of Medicine (R.M.C.), University of Virginia, Charlottesville; and Department of Family and Preventive Medicine, University of California San Diego, La Jolla (M.A.A.)
| | - Paula Q Barrett
- From the Center for Public Health Genomics (A.M., S.S.R.), Biostatistics Section, Department of Public Health Sciences (A.M.), Department of Pharmacology (N.A.G., D.A.B., P.Q.B.), and Division of Endocrinology and Metabolism and Department of Medicine (R.M.C.), University of Virginia, Charlottesville; and Department of Family and Preventive Medicine, University of California San Diego, La Jolla (M.A.A.).
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10
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Barrett PQ, Guagliardo NA, Klein PM, Hu C, Breault DT, Beenhakker MP. Role of voltage-gated calcium channels in the regulation of aldosterone production from zona glomerulosa cells of the adrenal cortex. J Physiol 2016; 594:5851-5860. [PMID: 26845064 DOI: 10.1113/jp271896] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 11/28/2015] [Indexed: 11/08/2022] Open
Abstract
Zona glomerulosa cells (ZG) of the adrenal gland constantly integrate fluctuating ionic, hormonal and paracrine signals to control the synthesis and secretion of aldosterone. These signals modulate Ca2+ levels, which provide the critical second messenger to drive steroid hormone production. Angiotensin II is a hormone known to modulate the activity of voltage-dependent L- and T-type Ca2+ channels that are expressed on the plasma membrane of ZG cells in many species. Because the ZG cell maintains a resting membrane voltage of approximately -85 mV and has been considered electrically silent, low voltage-activated T-type Ca2+ channels are assumed to provide the primary Ca2+ signal that drives aldosterone production. However, this view has recently been challenged by human genetic studies identifying somatic gain-of-function mutations in L-type CaV 1.3 channels in aldosterone-producing adenomas of patients with primary hyperaldosteronism. We provide a review of these assumptions and challenges, and update our understanding of the state of the ZG cell in a layer in which native cellular associations are preserved. This updated view of Ca2+ signalling in ZG cells provides a unifying mechanism that explains how transiently activating CaV 3.2 channels can generate a significant and recurring Ca2+ signal, and how CaV 1.3 channels may contribute to the Ca2+ signal that drives aldosterone production.
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Affiliation(s)
- Paula Q Barrett
- Department of Pharmacology, University of Virginia, Charlottesville, VA, 22947, USA
| | - Nick A Guagliardo
- Department of Pharmacology, University of Virginia, Charlottesville, VA, 22947, USA
| | - Peter M Klein
- Department of Pharmacology, University of Virginia, Charlottesville, VA, 22947, USA
| | - Changlong Hu
- Department of Physiology and Biophysics, School of Life Sciences, Institutes of Brain Science, Fudan University, Shanghai, 200433, China
| | - David T Breault
- Division of Endocrinology, Boston Children's Hospital, Boston, MA, 02115, USA
| | - Mark P Beenhakker
- Department of Pharmacology, University of Virginia, Charlottesville, VA, 22947, USA.
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11
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Guagliardo NA, Le TH, Bayliss DA, Breault DT, Barrett PQ. Abstract MP09: Adrenal-specific Deletion of TASK Channels Evokes Normal-Renin Hypertension. Hypertension 2015. [DOI: 10.1161/hyp.66.suppl_1.mp09] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objectives:
Dysregulation of aldosterone (Aldo) production is predicted to evoke major features of idiopathic primary hyperaldosteronism (IHA): low renin, elevated blood pressure and suppressed control by high Na. We have previously demonstrated in mice that global deletion of background TWIK-related acid-sensitive K (TASK) channels (TASK-1, TASK-3) effect a ~20mV decrease in the membrane potential of Zona Glomerulosa (ZG) cells to produce frank autonomous overproduction of Aldo, low renin, and hypertension (HT), mimicking the salient features of human IHA. In the current study, we ask if specific deletion of TASK channels in ZG cells is sufficient to produce hyperaldosteronism and the predicted sequela or if extra-adrenal deletion of TASK channels is required.
Design and Methods:
We generated a trigenic mouse-line (
AS
+Cre
::TASK-1
ff
::TASK-3
ff
, zT1T3KO) in which TASK-1 and TASK-3 subunits were specifically deleted in ZG cells. The renin-angiotensin-aldosterone system (RAAS) was evaluated in mice housed in metabolic cages and stabilized on various salt diets. Urinary Aldo concentration was measured and normalized to creatinine (ng Aldo/mg creatinine; 24 hr. urine collection). Blood pressure was recorded in conscious, freely moving mice using radio telemetry, and plasma renin concentration was measured from tail vein sampling.
Results:
Overproduction of aldosterone on normal-salt diet (0.3% Na) was modest in zT1T3KO mice compared to littermate controls (WT; WT 9.4; KO 11.8 ng/mg, 1.25-fold). Suppression of Aldo production by high-salt (2% Na) was blunted, exaggerating the difference in Aldo production between genotypes (WT 3.0; KO 7.4 ng/mg, 2.43-fold). zT1T3KO mice were hypertensive (mean MAP: WT 103.5; KO 113.1 mmHg), yet renin levels remained normal. Neither hyperaldosteronism nor HT could be corrected by angiotensin II receptor blockade, suggesting overproduction of Aldo and HT are independent of RAAS.
Conclusions:
Limiting TASK deletion to ZG cells results in normal renin HT driven by modest autonomous hyperaldosteronism, a stark contrast to the phenotypic features of IHA recapitulated by global TASK deletion. Together these mouse models provide insight into the role of ZG- vs extra-adrenal-dysfunction in the pathology of IHA.
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Affiliation(s)
| | - Thu H Le
- Univ of Virginia, Charlottesville, VA
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12
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Freedman BD, Kempna PB, Carlone DL, Shah M, Guagliardo NA, Barrett PQ, Gomez-Sanchez CE, Majzoub JA, Breault DT. Adrenocortical zonation results from lineage conversion of differentiated zona glomerulosa cells. Dev Cell 2013; 26:666-673. [PMID: 24035414 DOI: 10.1016/j.devcel.2013.07.016] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Revised: 06/11/2013] [Accepted: 07/17/2013] [Indexed: 02/06/2023]
Abstract
Lineage conversion of differentiated cells in response to hormonal feedback has yet to be described. To investigate this, we studied the adrenal cortex, which is composed of functionally distinct concentric layers that develop postnatally, the outer zona glomerulosa (zG) and the inner zona fasciculata (zF). These layers have separate functions, are continuously renewed in response to physiological demands, and are regulated by discrete hormonal feedback loops. Their cellular origin, lineage relationship, and renewal mechanism, however, remain poorly understood. Cell-fate mapping and gene-deletion studies using zG-specific Cre expression demonstrate that differentiated zG cells undergo lineage conversion into zF cells. In addition, zG maintenance is dependent on the master transcriptional regulator Steroidogenic Factor 1 (SF-1), and zG-specific Sf-1 deletion prevents lineage conversion. These findings demonstrate that adrenocortical zonation and regeneration result from lineage conversion and may provide a paradigm for homeostatic cellular renewal in other tissues.
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Affiliation(s)
- Bethany D Freedman
- Division of Endocrinology, Boston Children's Hospital, Boston, MA 02115 USA.,Department of Pediatrics, Harvard Medical School, Boston, MA 02115 USA
| | - Petra Bukovac Kempna
- Division of Endocrinology, Boston Children's Hospital, Boston, MA 02115 USA.,Department of Pediatrics, Harvard Medical School, Boston, MA 02115 USA
| | - Diana L Carlone
- Division of Endocrinology, Boston Children's Hospital, Boston, MA 02115 USA.,Department of Pediatrics, Harvard Medical School, Boston, MA 02115 USA
| | - Manasvi Shah
- Division of Endocrinology, Boston Children's Hospital, Boston, MA 02115 USA.,Department of Pediatrics, Harvard Medical School, Boston, MA 02115 USA
| | - Nick A Guagliardo
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA, 22908 USA
| | - Paula Q Barrett
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA, 22908 USA
| | - Celso E Gomez-Sanchez
- Department of Medicine, University of Mississippi Medical Center, Jackson, MS 39216 USA
| | - Joseph A Majzoub
- Division of Endocrinology, Boston Children's Hospital, Boston, MA 02115 USA.,Department of Pediatrics, Harvard Medical School, Boston, MA 02115 USA
| | - David T Breault
- Division of Endocrinology, Boston Children's Hospital, Boston, MA 02115 USA.,Department of Pediatrics, Harvard Medical School, Boston, MA 02115 USA.,Harvard Stem Cell Institute, Cambridge, MA 02138 USA
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13
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Abstract
Aldosterone produced by adrenal zona glomerulosa (ZG) cells plays an important role in maintaining salt/water balance and, hence, blood pressure homeostasis. However, when dysregulated, aldosterone advances renal and cardiovascular disease states. Multiple steps in the steroidogenic pathway require Ca(2+), and the sustained production of aldosterone depends on maintained Ca(2+) entry into the ZG cell. Nevertheless, the recorded membrane potential of isolated ZG cells is extremely hyperpolarized, allowing the opening of only a small fraction of low-voltage-activated Ca(2+) channels of the Ca(v)3.x family, the major Ca(2+) conductance on the ZG cell membrane. As a consequence, to activate sufficient Ca(2+) channels to sustain the production of aldosterone, aldosterone secretagogs would be required to affect large decreases in membrane voltage, a requirement that is inconsistent with the exquisite sensitivity of aldosterone production in vivo to small changes (0.1 mm) in extracellular K(+). In this review, we evaluate the contribution of membrane voltage and voltage-dependent Ca(2+) channels to the control of aldosterone production and consider data highlighting the electrical excitability of the ZG cell. This intrinsic capacity of ZG cells to behave as electrical oscillators provides a platform from which to generate a recurring Ca(2+) signal that is compatible with the lengthy time course of steroidogenesis and provides an alternative model for the physiological regulation of aldosterone production that permits both amplitude and temporal modulation of the Ca(2+) signal.
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Affiliation(s)
- Nick A Guagliardo
- Department of Pharmacology, University of Virginia, P.O. Box 800735, Jordan Hall 5th Floor, 5058, Charlottesville, Virginia 22908, USA
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14
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Hu C, Rusin CG, Tan Z, Guagliardo NA, Barrett PQ. Zona glomerulosa cells of the mouse adrenal cortex are intrinsic electrical oscillators. J Clin Invest 2012; 122:2046-53. [PMID: 22546854 DOI: 10.1172/jci61996] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Accepted: 03/14/2012] [Indexed: 02/06/2023] Open
Abstract
Aldosterone, which plays a central role in the regulation of blood pressure, is produced by zona glomerulosa (ZG) cells of the adrenal gland. When dysregulated, aldosterone is pathogenic and contributes to the development and progression of cardiovascular and renal disease. Although sustained production of aldosterone requires persistent Ca2+ entry through low-voltage activated Ca2+ channels, isolated ZG cells are considered nonexcitable, with recorded membrane voltages that are too hyperpolarized to permit Ca2+ entry. Here, we show that mouse ZG cells within adrenal slices spontaneously generate membrane potential oscillations of low periodicity. This innate electrical excitability of ZG cells provides a platform for the production of a recurrent Ca2+ signal that can be controlled by Ang II and extracellular potassium, the 2 major regulators of aldosterone production. We conclude that native ZG cells are electrical oscillators, and that this behavior provides what we believe to be a new molecular explanation for the control of Ca2+ entry in these steroidogenic cells.
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Affiliation(s)
- Changlong Hu
- School of Life Sciences, State Key Laboratory of Medical Neurobiology and Institutes of Brain Science, Fudan University, Shanghai, China
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15
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Guagliardo NA, Yao J, Hu C, Schertz EM, Tyson DA, Carey RM, Bayliss DA, Barrett PQ. TASK-3 channel deletion in mice recapitulates low-renin essential hypertension. Hypertension 2012; 59:999-1005. [PMID: 22493079 DOI: 10.1161/hypertensionaha.111.189662] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Idiopathic primary hyperaldosteronism (IHA) and low-renin essential hypertension (LREH) are common forms of hypertension, characterized by an elevated aldosterone-renin ratio and hypersensitivity to angiotensin II. They are suggested to be 2 states within a disease spectrum that progresses from LREH to IHA as the control of aldosterone production by the renin-angiotensin system is weakened. The mechanism(s) that drives this progression remains unknown. Deletion of Twik-related acid-sensitive K(+) channels (TASK) subunits, TASK-1 and TASK-3, in mice (T1T3KO) produces a model of human IHA. Here, we determine the effect of deleting only TASK-3 (T3KO) on the control of aldosterone production and blood pressure. We find that T3KO mice recapitulate key characteristics of human LREH, salt-sensitive hypertension, mild overproduction of aldosterone, decreased plasma-renin concentration with elevated aldosterone:renin ratio, hypersensitivity to endogenous and exogenous angiotensin II, and failure to suppress aldosterone production with dietary sodium loading. The relative differences in levels of aldosterone output and aldosterone:renin ratio and in autonomy of aldosterone production between T1T3KO and T3KO mice are reminiscent of differences in human hypertensive patients with LREH and IHA. Our studies establish a model of LREH and suggest that loss of TASK channel activity may be one mechanism that advances the syndrome of low renin hypertension.
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Affiliation(s)
- Nick A Guagliardo
- Department of Pharmacology, University of Virginia, School of Medicine, Charlottesville, VA 22908, USA
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16
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Guagliardo NA, Yao J, Bayliss DA, Barrett PQ. TASK channels are not required to mount an aldosterone secretory response to metabolic acidosis in mice. Mol Cell Endocrinol 2011; 336:47-52. [PMID: 21111026 PMCID: PMC3057342 DOI: 10.1016/j.mce.2010.11.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Revised: 11/15/2010] [Accepted: 11/15/2010] [Indexed: 12/31/2022]
Abstract
The stimulation of aldosterone production by acidosis enhances proton excretion and serves to limit disturbances in systemic acid-base equilibrium. Yet, the mechanisms by which protons stimulate aldosterone production from cells of the adrenal cortex remain largely unknown. TWIK-related acid sensitive K channels (TASK) are inhibited by extracellular protons within the physiological range and have emerged as important regulators of aldosterone production in the adrenal cortex. Here we show that congenic C57BL/6J mice with genetic deletion of TASK-1 (K(2P)3.1) and TASK-3 (K(2P)9.1) channel subunits overproduce aldosterone and display an enhanced sensitivity to steroidogenic stimuli, including a more pronounced steroidogenic response to chronic NH(4)Cl loading. Thus, we conclude that TASK channels are not required for the stimulation of aldosterone production by protons but their inhibition by physiological acidosis may contribute to full expression of the steroidogenic response.
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Affiliation(s)
- Nick A. Guagliardo
- University of Virginia, Department of Pharmacology, 1340 Jefferson Park Ave. Charlottesville, VA 22908, USA
| | - Junlan Yao
- University of Virginia, Department of Pharmacology, 1340 Jefferson Park Ave. Charlottesville, VA 22908, USA
| | - Douglas A. Bayliss
- University of Virginia, Department of Pharmacology, 1340 Jefferson Park Ave. Charlottesville, VA 22908, USA
| | - Paula Q. Barrett
- University of Virginia, Department of Pharmacology, 1340 Jefferson Park Ave. Charlottesville, VA 22908, USA
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17
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Guagliardo NA, West KN, McCluskey LP, Hill DL. Attenuation of peripheral salt taste responses and local immune function contralateral to gustatory nerve injury: effects of aldosterone. Am J Physiol Regul Integr Comp Physiol 2009; 297:R1103-10. [PMID: 19675282 DOI: 10.1152/ajpregu.00219.2009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Dietary sodium restriction coupled with axotomy of the rat chorda tympani nerve (CTX) results in selectively attenuated taste responses to sodium salts in the contralateral, intact chorda tympani nerve. Converging evidence indicates that sodium deficiency also diminishes the activated macrophage response to injury on both the sectioned and contralateral, intact sides of the tongue. Because a sodium-restricted diet causes a robust increase in circulating aldosterone, we tested the hypothesis that changes in neurophysiological and immune responses contralateral to the CTX could be mimicked by aldosterone administration instead of the low-sodium diet. Taste responses in rats with CTX and supplemental aldosterone for 4-6 days were similar to rats with CTX and dietary sodium restriction. Responses to sodium salts were as much as 50% lower compared with sham-operated and vehicle-supplemented rats. The group-related functional differences were eliminated with lingual application of amiloride, suggesting that a major transduction pathway affected was through epithelial sodium channels. Consistent with the functional results, few macrophages were observed on either side of the tongue in rats with CTX and aldosterone. In contrast, macrophages were elevated on both sides of the tongue in rats with CTX and the vehicle. These results show that sodium deficiency or administration of aldosterone suppresses the immune response to neural injury, resulting in attenuation of peripheral gustatory function. They also show a potential key link among downstream consequences of sodium imbalance, taste function, and immune activity.
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Affiliation(s)
- Nick A Guagliardo
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia 22904, USA
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18
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Abstract
Taste buds are dependent on innervation for normal morphology and function. Fungiform taste bud degeneration after chorda tympani nerve injury has been well documented in rats, hamsters, and gerbils. The current study examines fungiform taste bud distribution and structure in adult C57BL/6J mice from both intact taste systems and after unilateral chorda-lingual nerve transection. Fungiform taste buds were visualized and measured with the aid of cytokeratin 8. In control mice, taste buds were smaller and more abundant on the anterior tip (<1 mm) of the tongue. By 5 days after nerve transection taste buds were smaller and fewer on the side of the tongue ipsilateral to the transection and continued to decrease in both size and number until 15 days posttransection. Degenerating fungiform taste buds were smaller due to a loss of taste bud cells rather than changes in taste bud morphology. While almost all taste buds disappeared in more posterior fungiform papillae by 15 days posttransection, the anterior tip of the tongue retained nearly half of its taste buds compared to intact mice. Surviving taste buds could not be explained by an apparent innervation from the remaining intact nerves. Contralateral effects of nerve transection were also observed; taste buds were larger due to an increase in the number of taste bud cells. These data are the first to characterize adult mouse fungiform taste buds and subsequent degeneration after unilateral nerve transection. They provide the basis for more mechanistic studies in which genetically engineered mice can be used.
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Affiliation(s)
- Nick A Guagliardo
- Department of Psychology, University of Virginia, Charlottesville, Virginia 22904-4400, USA
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19
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Abstract
Water-restricted rats were trained to press one lever after KCl presentation and the other lever after distilled water. Water reinforcement was given after each correct response, and a time-out followed each incorrect response. Rats were trained and tested on KCl stimuli of varying concentrations. Threshold was defined as the KCl concentration corresponding to 1/2 the maximum asymptote of performance for each rat. The geometric mean KCl detection threshold for all rats was 0.033 M KCl. Rats that had the chorda tympani nerve (CT) bilaterally transected showed an average increase in KCl threshold of approximately 0.60 log10 units, whereas sham-operated rats showed no change. Control rats retested with 100 microM amiloride added to all KCl concentrations and water displayed no change in threshold. These results suggest that although the CT contributes significantly to the rat's sensitivity to KCl, amiloride-sensitive taste transduction pathways do not.
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Affiliation(s)
- L C Geran
- Department of Psychology, University of Florida, Gainesville 32611-2250, USA
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20
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St John SJ, Markison S, Guagliardo NA, Hackenberg TD, Spector AC. Chorda tympani transection and selective desalivation differentially disrupt two-lever salt discrimination performance in rats. Behav Neurosci 1997; 111:450-9. [PMID: 9106683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Water-restricted rats were trained to press 1 of 2 levers if a sampled stimulus was NaCl and the other lever if the stimulus was KCl (0.05, 0.1, or 0.2 M). Responses were reinforced with water. After training, the average rate of correct responses was 90%. Performance was unchanged following sham surgery. Chorda tympani (CT) transection reduced average discrimination performance to 67.7% correct, and extirpation of the sublingual and submaxillary salivary glands reduced average performance to 80% correct. Although selective desalivation moderately reduced discriminability, a disrupted salivary environment does not explain the effects of CT transection. More likely, the discrimination deficit in CT-transected rats reflects a loss of critical taste input conveyed by the CT about salts.
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Affiliation(s)
- S J St John
- Department of Psychology, University of Florida, Gainesville 32611-2250, USA
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St. John SJ, Markison S, Guagliardo NA, Hackenberg TD, Spector AC. Chorda tympani transection and selective desalivation differentially disrupt two-lever salt discrimination performance in rats. Behav Neurosci 1997. [DOI: 10.1037/0735-7044.111.2.450] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Spector AC, Guagliardo NA, St John SJ. Amiloride disrupts NaCl versus KCl discrimination performance: implications for salt taste coding in rats. J Neurosci 1996; 16:8115-22. [PMID: 8987836 PMCID: PMC6579222] [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] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Amiloride, an epithelial sodium channel blocker, suppresses the responsiveness of narrowly tuned sodium-responsive taste afferents when orally applied in the rat. Broadly tuned salt-responsive taste afferents, which respond to sodium and nonsodium salts and acids, are relatively unaffected by the drug. We used amiloride treatment to examine the consequences of the specific removal of input from narrowly tuned sodium-responsive afferents on taste discrimination. Five water-restricted rats were trained in a gustometer to press one lever after licking NaCl and another lever after licking KCl across a range of concentrations (0.05, 0.1, and 0.2 M). Correct responses were rewarded with brief water access, and incorrect responses were punished with a time-out. After training, animals averaged about 90% correct responses and maintained competent performance during subsequent control sessions. Amiloride was then placed in all solutions at a given concentration (1-100 microM) for single test sessions. Control sessions were interposed between amiloride sessions. At high amiloride concentrations, overall responding was reduced to 50% correct and progressively improved as the drug concentration was lowered. The sigmoidal dose-response functions corresponded quantitatively with electrophysiological findings. Performance deficits occurred primarily with NaCl and were concentration dependent; performance during KCl trials was relatively undisturbed by amiloride adulteration. At high amiloride concentrations, rats treated NaCl as if it were KCl. Given that amiloride is tasteless to the rat, these results provide convincing evidence of the importance of narrowly tuned afferents in the discrimination between sodium and nonsodium salts and suggest that this is a general coding principle in the gustatory system.
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Affiliation(s)
- A C Spector
- Department of Psychology, University of Florida, Gainesville, Florida 32611, USA
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