1
|
Takayama Y, Tominaga M. Interaction between TRP channels and anoctamins. Cell Calcium 2024; 121:102912. [PMID: 38823351 DOI: 10.1016/j.ceca.2024.102912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 05/27/2024] [Accepted: 05/27/2024] [Indexed: 06/03/2024]
Abstract
Anoctamin 1 (ANO1) binds to transient receptor potential (TRP) channels (protein-protein interaction) and then is activated by TRP channels (functional interaction). TRP channels are non-selective cation channels that are expressed throughout the body and play roles in multiple physiological functions. Studies on TRP channels increased after the identification of TRP vanilloid 1 (TRPV1) in 1997. Calcium-activated chloride channel anoctamin 1 (ANO1, also called TMEM16A and DOG1) was identified in 2008. ANO1 plays a major role in TRP channel-mediated functions, as first shown in 2014 with the demonstration of a protein-protein interaction between TRPV4 and ANO1. In cells that co-express TRP channels and ANO1, calcium entering cells through activated TRP channels causes ANO1 activation. Therefore, in many tissues, the physiological functions related to TRP channels are modulated through chloride flux associated with ANO1 activation. In this review, we summarize the latest understanding of TRP-ANO1 interactions, particularly interaction of ANO1 with TRPV4, TRP canonical 6 (TRPC6), TRPV3, TRPV1, and TRPC2 in the salivary glands, blood vessels, skin keratinocytes, primary sensory neurons, and vomeronasal organs, respectively.
Collapse
Affiliation(s)
- Yasunori Takayama
- Department of Physiology, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa, Tokyo, Japan.
| | - Makoto Tominaga
- Division of Cell Signaling, National Institute for Physiological Sciences, National Institutes of Natural Sciences, 5-1 Aza-Higashiyama, Myodaiji, Okazaki, Aichi, Japan; Thermal Biology Group, Exploratory Research Center on Life and Living Systems, National Institutes of Natural Sciences, 5-1 Aza-Higashiyama, Myodaiji, Okazaki, Aichi, Japan; Thermal Biology Research Group, Nagoya Advanced Research and Development Center, Nagoya City University, Kawasumi 1, Mizuho-cho, Mizuho-ku, Nagoya, Aichi, Japan.
| |
Collapse
|
2
|
Davis MJ, Castorena-Gonzalez JA, Zawieja SD. Electric field stimulation unmasks a subtle role for T-type calcium channels in regulating lymphatic contraction. Sci Rep 2023; 13:15862. [PMID: 37739992 PMCID: PMC10516884 DOI: 10.1038/s41598-023-42877-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 09/15/2023] [Indexed: 09/24/2023] Open
Abstract
We previously identified two isoforms of T-type, voltage-gated calcium (Cav3) channels (Cav3.1, Cav3.2) that are functionally expressed in murine lymphatic muscle cells; however, contractile tests of lymphatic vessels from single and double Cav3 knock-out (DKO) mice, exhibited nearly identical parameters of spontaneous twitch contractions as wild-type (WT) vessels, suggesting that Cav3 channels play no significant role. Here, we considered the possibility that the contribution of Cav3 channels might be too subtle to detect in standard contraction analyses. We compared the sensitivity of lymphatic vessels from WT and Cav3 DKO mice to the L-type calcium channel (Cav1.2) inhibitor nifedipine and found that the latter vessels were significantly more sensitive to inhibition, suggesting that the contribution of Cav3 channels might normally be masked by Cav1.2 channel activity. We hypothesized that shifting the resting membrane potential (Vm) of lymphatic muscle to a more negative voltage might enhance the contribution of Cav3 channels. Because even slight hyperpolarization is known to completely silence spontaneous contractions, we devised a method to evoke nerve-independent, twitch contractions from mouse lymphatic vessels using single, short pulses of electric field stimulation (EFS). TTX was present throughout to block the potential contributions of voltage-gated Na+ channels in perivascular nerves and lymphatic muscle. In WT vessels, EFS evoked single contractions that were comparable in amplitude and degree of entrainment to those occurring spontaneously. When Cav1.2 channels were blocked or deleted, only small residual EFS-evoked contractions (~ 5% of normal amplitude) were present. These residual, EFS-evoked contractions were enhanced (to 10-15%) by the KATP channel activator pinacidil (PIN) but were absent in Cav3 DKO vessels. Our results point to a subtle contribution of Cav3 channels to lymphatic contractions that can be unmasked in the absence of Cav1.2 channel activity and when the resting Vm is more hyperpolarized than normal.
Collapse
Affiliation(s)
- Michael J Davis
- Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, One Hospital Drive, MA415 Medical Sciences Building, Columbia, MO, 65212, USA.
| | | | - Scott D Zawieja
- Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, One Hospital Drive, MA415 Medical Sciences Building, Columbia, MO, 65212, USA
| |
Collapse
|
3
|
Davis MJ, Castorena-Gonzalez JA, Zawieja SD. Electric field stimulation unmasks a subtle role for T-type calcium channels in regulating lymphatic contraction. RESEARCH SQUARE 2023:rs.3.rs-2938440. [PMID: 37333279 PMCID: PMC10275045 DOI: 10.21203/rs.3.rs-2938440/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
We previously identified two isoforms of T-type, voltage-gated calcium (Ca v 3) channels (Ca v 3.1, Ca v 3.2) that are functionally expressed in murine lymphatic muscle cells; however, contractile tests of lymphatic vessels from single and double Ca v 3 knock-out (DKO) mice, exhibited nearly identical parameters of spontaneous twitch contractions as wild-type (WT) vessels, suggesting that Ca v 3 channels play no significant role. Here, we considered the possibility that the contribution of Ca v 3 channels might be too subtle to detect in standard contraction analyses. We compared the sensitivity of lymphatic vessels from WT and Ca v 3 DKO mice to the L-type calcium channel (Ca v 1.2) inhibitor nifedipine and found that the latter vessels were significantly more sensitive to inhibition, suggesting that the contribution of Ca v 3 channels might normally be masked by Ca v 1.2 channel activity. We hypothesized that shifting the resting membrane potential (Vm) of lymphatic muscle to a more negative voltage might enhance the contribution of Ca v 3 channels. Because even slight hyperpolarization is known to completely silence spontaneous contractions, we devised a method to evoke nerve-independent, twitch contractions from mouse lymphatic vessels using single, short pulses of electric field stimulation (EFS). TTX was present throughout to block the potential contributions of voltage-gated Na + channels in perivascular nerves and lymphatic muscle. In WT vessels, EFS evoked single contractions that were comparable in amplitude and degree of entrainment to those occurring spontaneously. When Ca v 1.2 channels were blocked or deleted, only small residual EFS-evoked contractions (~ 5% of normal amplitude) were present. These residual, EFS-evoked contractions were enhanced (to 10-15%) by the K ATP channel activator pinacidil (PIN) but were absent in Ca v 3 DKO vessels. Our results point to a subtle contribution of Ca v 3 channels to lymphatic contractions that can be unmasked in the absence of Ca v 1.2 channel activity and when the resting Vm is more hyperpolarized than normal.
Collapse
|
4
|
Park J, Proux C, Ehanno W, Réthoré L, Vessières E, Bourreau J, Favre J, Kauffenstein G, Mattei C, Tricoire-Leignel H, Henrion D, Legendre C, Legros C. Tetrodotoxin Decreases the Contractility of Mesenteric Arteries, Revealing the Contribution of Voltage-Gated Na + Channels in Vascular Tone Regulation. Mar Drugs 2023; 21:md21030196. [PMID: 36976245 PMCID: PMC10059581 DOI: 10.3390/md21030196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/11/2023] [Accepted: 03/20/2023] [Indexed: 03/29/2023] Open
Abstract
Tetrodotoxin (TTX) poisoning through the consumption of contaminated fish leads to lethal symptoms, including severe hypotension. This TTX-induced hypotension is likely due to the downfall of peripheral arterial resistance through direct or indirect effects on adrenergic signaling. TTX is a high-affinity blocker of voltage-gated Na+ (NaV) channels. In arteries, NaV channels are expressed in sympathetic nerve endings, both in the intima and media. In this present work, we aimed to decipher the role of NaV channels in vascular tone using TTX. We first characterized the expression of NaV channels in the aorta, a model of conduction arteries, and in mesenteric arteries (MA), a model of resistance arteries, in C57Bl/6J mice, by Western blot, immunochemistry, and absolute RT-qPCR. Our data showed that these channels are expressed in both endothelium and media of aorta and MA, in which scn2a and scn1b were the most abundant transcripts, suggesting that murine vascular NaV channels consist of NaV1.2 channel subtype with NaVβ1 auxiliary subunit. Using myography, we showed that TTX (1 µM) induced complete vasorelaxation in MA in the presence of veratridine and cocktails of antagonists (prazosin and atropine with or without suramin) that suppressed the effects of neurotransmitter release. In addition, TTX (1 µM) strongly potentiated the flow-mediated dilation response of isolated MA. Altogether, our data showed that TTX blocks NaV channels in resistance arteries and consecutively decreases vascular tone. This could explain the drop in total peripheral resistance observed during mammal tetrodotoxications.
Collapse
Affiliation(s)
- Joohee Park
- INSERM, CNRS, MITOVASC, Equipe CarME, SFR ICAT, University Angers, 49000 Angers, France
| | - Coralyne Proux
- INSERM, CNRS, MITOVASC, Equipe CarME, SFR ICAT, University Angers, 49000 Angers, France
| | - William Ehanno
- INSERM, CNRS, MITOVASC, Equipe CarME, SFR ICAT, University Angers, 49000 Angers, France
| | - Léa Réthoré
- INSERM, CNRS, MITOVASC, Equipe CarME, SFR ICAT, University Angers, 49000 Angers, France
| | - Emilie Vessières
- INSERM, CNRS, MITOVASC, Equipe CarME, SFR ICAT, University Angers, 49000 Angers, France
| | - Jennifer Bourreau
- INSERM, CNRS, MITOVASC, Equipe CarME, SFR ICAT, University Angers, 49000 Angers, France
| | - Julie Favre
- INSERM, CNRS, MITOVASC, Equipe CarME, SFR ICAT, University Angers, 49000 Angers, France
- UMR INSERM 1121, CRBS, Strasbourg University, 67000 Strasbourg, France
| | - Gilles Kauffenstein
- INSERM, CNRS, MITOVASC, Equipe CarME, SFR ICAT, University Angers, 49000 Angers, France
- UMR INSERM 1260, CRBS, Strasbourg University, 67084 Strasbourg, France
| | - César Mattei
- INSERM, CNRS, MITOVASC, Equipe CarME, SFR ICAT, University Angers, 49000 Angers, France
| | | | - Daniel Henrion
- INSERM, CNRS, MITOVASC, Equipe CarME, SFR ICAT, University Angers, 49000 Angers, France
| | - Claire Legendre
- INSERM, CNRS, MITOVASC, Equipe CarME, SFR ICAT, University Angers, 49000 Angers, France
| | - Christian Legros
- INSERM, CNRS, MITOVASC, Equipe CarME, SFR ICAT, University Angers, 49000 Angers, France
| |
Collapse
|
5
|
Hypoxic Conditions Promote Rhythmic Contractile Oscillations Mediated by Voltage-Gated Sodium Channels Activation in Human Arteries. Int J Mol Sci 2021; 22:ijms22052570. [PMID: 33806419 PMCID: PMC7961413 DOI: 10.3390/ijms22052570] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 02/24/2021] [Accepted: 02/28/2021] [Indexed: 11/17/2022] Open
Abstract
Arterial smooth muscle exhibits rhythmic oscillatory contractions called vasomotion and believed to be a protective mechanism against tissue hypoperfusion or hypoxia. Oscillations of vascular tone depend on voltage and follow oscillations of the membrane potential. Voltage-gated sodium channels (Nav), responsible for the initiation and propagation of action potentials in excitable cells, have also been evidenced both in animal and human vascular smooth muscle cells (SMCs). For example, they contribute to arterial contraction in rats, but their physiopathological relevance has not been established in human vessels. In the present study, we investigated the functional role of Nav in the human artery. Experiments were performed on human uterine arteries obtained after hysterectomy and on SMCs dissociated from these arteries. In SMCs, we recorded a tetrodotoxin (TTX)-sensitive and fast inactivating voltage-dependent INa current. Various Nav genes, encoding α-subunit isoforms sensitive (Nav 1.2; 1.3; 1.7) and resistant (Nav 1.5) to TTX, were detected both in arterial tissue and in SMCs. Nav channels immunostaining showed uniform distribution in SMCs and endothelial cells. On arterial tissue, we recorded variations of isometric tension, ex vivo, in response to various agonists and antagonists. In arterial rings placed under hypoxic conditions, the depolarizing agent KCl and veratridine, a specific Nav channels agonist, both induced a sustained contraction overlaid with rhythmic oscillations of tension. After suppression of sympathetic control either by blocking the release of catecholamine or by antagonizing the target adrenergic response, rhythmic activity persisted while the sustained contraction was abolished. This rhythmic activity of the arteries was suppressed by TTX but, in contrast, only attenuated by antagonists of calcium channels, Na+/Ca2+ exchanger, Na+/K+-ATPase and the cardiac Nav channel. These results highlight the role of Nav as a novel key element in the vasomotion of human arteries. Hypoxia promotes activation of Nav channels involved in the initiation of rhythmic oscillatory contractile activity.
Collapse
|
6
|
Rivero-Echeto MC, Perissinotti PP, González-Inchauspe C, Kargieman L, Bisagno V, Urbano FJ. Simultaneous administration of cocaine and caffeine dysregulates HCN and T-type channels. Psychopharmacology (Berl) 2021; 238:787-810. [PMID: 33241481 PMCID: PMC7688300 DOI: 10.1007/s00213-020-05731-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 11/18/2020] [Indexed: 12/13/2022]
Abstract
RATIONALE The abuse of psychostimulants has adverse consequences on the physiology of the central nervous system. In Argentina, and other South American countries, coca paste or "PACO" (cocaine and caffeine are its major components) is massively consumed with deleterious clinical consequences for the health and well-being of the general population. A scant number of studies have addressed the consequences of stimulant combination of cocaine and caffeine on the physiology of the somatosensory thalamocortical (ThCo) system. OBJECTIVES Our aim was to study ion conductances that have important implications regulating sleep-wake states 24-h after an acute or chronic binge-like administration of a cocaine and caffeine mixture following previously analyzed pasta base samples ("PACO"-like binge") using mice. METHODS We randomly injected (i.p.) male C57BL/6JFcen mice with a binge-like psychostimulants regimen during either 1 day (acute) or 1 day on/1 day off during 13 days for a total of 7 binges (chronic). Single-cell patch-clamp recordings of VB neurons were performed in thalamocortical slices 24 h after the last psychostimulant injection. We also recorded EEG/EMG from mice 24 h after being systemically treated with chronic administration of cocaine + caffeine versus saline, vehicle. RESULTS Our results showed notorious changes in the intrinsic properties of the VB nucleus neurons that persist after 24-h of either acute or chronic binge administrations of combined cocaine and caffeine ("PACO"-like binge). Functional dysregulation of HCN (hyperpolarization-activated cyclic nucleotide-gated) and T-type VGC (voltage-gated calcium) channels was described 24-h after acute/chronic "PACO"-like administrations. Furthermore, intracellular basal [Ca2+] disturbances resulted a key factor that modulated the availability and the activation of T-type channels, altering T-type "window currents." As a result, all these changes ultimately shaped the low-threshold spikes (LTS)-associated Ca2+ transients, regulated the membrane excitability, and altered sleep-wake transitions. CONCLUSION Our results suggest that deleterious consequences of stimulants cocaine and caffeine combination on the thalamocortical physiology as a whole might be related to potential neurotoxic effects of soaring intracellular [Ca2+].
Collapse
Affiliation(s)
- María Celeste Rivero-Echeto
- grid.7345.50000 0001 0056 1981CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Ciudad de Buenos Aires, Argentina
| | - Paula P. Perissinotti
- grid.7345.50000 0001 0056 1981CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Ciudad de Buenos Aires, Argentina
| | - Carlota González-Inchauspe
- grid.7345.50000 0001 0056 1981CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Ciudad de Buenos Aires, Argentina
| | - Lucila Kargieman
- grid.7345.50000 0001 0056 1981CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Ciudad de Buenos Aires, Argentina
| | - Verónica Bisagno
- grid.7345.50000 0001 0056 1981CONICET-Universidad de Buenos Aires, Instituto de Investigaciones Farmacológicas (ININFA), Ciudad de Buenos Aires, Argentina
| | - Francisco J. Urbano
- grid.7345.50000 0001 0056 1981CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Ciudad de Buenos Aires, Argentina ,grid.7345.50000 0001 0056 1981Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular “Dr. Héctor Maldonado”, Ciudad de Buenos Aires, Argentina ,grid.7345.50000 0001 0056 1981IFIBYNE (UBA-CONICET), Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA Ciudad Autónoma de Buenos Aires, Argentina
| |
Collapse
|
7
|
Sarkar J, Chakraborti T, Pramanik PK, Ghosh P, Mandal A, Chakraborti S. PKCζ-NADPH Oxidase-PKCα Dependent Kv1.5 Phosphorylation by Endothelin-1 Modulates Nav1.5-NCX1-Cav1.2 Axis in Stimulating Ca 2+ Level in Caveolae of Pulmonary Artery Smooth Muscle Cells. Cell Biochem Biophys 2020; 79:57-71. [PMID: 33095400 DOI: 10.1007/s12013-020-00954-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/13/2020] [Indexed: 11/29/2022]
Abstract
Endothelin-1 (ET-1) is a potent endogenously derived vasoconstrictor, which increases pulmonary hypertension via stimulation of [Ca2+]i level in pulmonary artery smooth muscle cells (PASMCs). In this communication, we sought to investigate the mechanism by which ET-1 causes stimulation of Ca2+ concentration in caveolae vesicles of bovine PASMCs (BPASMCs). ET-1 activates PKC-α in the caveolae vesicles by O2.- derived from PKCζ-NADPH oxidase dependent pathway. PKC-α phosphorylates Kv1.5 channels leading to a marked stimulation of Na+ and Ca2+ concentration in the caveolae vesicles. The stimulation of Ca2+ concentration in the caveolae vesicles by ET-1 occurs predominantly via Cav1.2 channels. Additionally, an increase in Na+ concentration by ET-1 due to stimulation of Nav1.5 channels marginally increases Ca2+ level in the caveolae vesicles via reverse-mode Na+/Ca2+ exchanger (NCX-1) and also through "slip-mode conductance" Nav1.5 channels. 4-AP, a well-known inhibitor of Kv channels, also increases Ca2+ concentration in the caveolae vesicles via Cav1.2 channels, reverse-mode NCX-1 and Nav1.5 channels by phosphorylation independent modulation of Kv1.5 channels without the involvement of PKCζ-NADPH oxidase-PKCα signaling axis. Overall, PKCζ-NADPH oxidase-PKCα dependent phosphorylation of Kv1.5 by ET-1 modulates Nav1.5-NCX1-Cav1.2 axis for stimulation of Ca2+ concentration in caveolae vesicles of BPASMCs, which provides a crucial mechanism for better understanding of ET-1-mediated modulation of pulmonary vascular tone.
Collapse
Affiliation(s)
- Jaganmay Sarkar
- Department of Biochemistry and Biophysics, University of Kalyani, Kalyani, West Bengal, 741235, India
| | - Tapati Chakraborti
- Department of Biochemistry and Biophysics, University of Kalyani, Kalyani, West Bengal, 741235, India
| | - Pijush Kanti Pramanik
- Department of Biochemistry and Biophysics, University of Kalyani, Kalyani, West Bengal, 741235, India
| | - Priyanka Ghosh
- Department of Biochemistry and Biophysics, University of Kalyani, Kalyani, West Bengal, 741235, India
| | - Amritlal Mandal
- Department of Biochemistry and Biophysics, University of Kalyani, Kalyani, West Bengal, 741235, India
| | - Sajal Chakraborti
- Department of Biochemistry and Biophysics, University of Kalyani, Kalyani, West Bengal, 741235, India.
| |
Collapse
|
8
|
Vornanen M. Feeling the heat: source–sink mismatch as a mechanism underlying the failure of thermal tolerance. J Exp Biol 2020; 223:223/16/jeb225680. [DOI: 10.1242/jeb.225680] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
ABSTRACT
A mechanistic explanation for the tolerance limits of animals at high temperatures is still missing, but one potential target for thermal failure is the electrical signaling off cells and tissues. With this in mind, here I review the effects of high temperature on the electrical excitability of heart, muscle and nerves, and refine a hypothesis regarding high temperature-induced failure of electrical excitation and signal transfer [the temperature-dependent deterioration of electrical excitability (TDEE) hypothesis]. A central tenet of the hypothesis is temperature-dependent mismatch between the depolarizing ion current (i.e. source) of the signaling cell and the repolarizing ion current (i.e. sink) of the receiving cell, which prevents the generation of action potentials (APs) in the latter. A source–sink mismatch can develop in heart, muscles and nerves at high temperatures owing to opposite effects of temperature on source and sink currents. AP propagation is more likely to fail at the sites of structural discontinuities, including electrically coupled cells, synapses and branching points of nerves and muscle, which impose an increased demand of inward current. At these sites, temperature-induced source–sink mismatch can reduce AP frequency, resulting in low-pass filtering or a complete block of signal transmission. In principle, this hypothesis can explain a number of heat-induced effects, including reduced heart rate, reduced synaptic transmission between neurons and reduced impulse transfer from neurons to muscles. The hypothesis is equally valid for ectothermic and endothermic animals, and for both aquatic and terrestrial species. Importantly, the hypothesis is strictly mechanistic and lends itself to experimental falsification.
Collapse
Affiliation(s)
- Matti Vornanen
- Department of Environmental and Biological Sciences , University of Eastern Finland, 80101 Joensuu, Finland
| |
Collapse
|
9
|
Fatoyinbo HO, Brown RG, Simpson DJW, van Brunt B. Numerical Bifurcation Analysis of Pacemaker Dynamics in a Model of Smooth Muscle Cells. Bull Math Biol 2020; 82:95. [PMID: 32676881 DOI: 10.1007/s11538-020-00771-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 06/26/2020] [Indexed: 11/26/2022]
Abstract
Evidence from experimental studies shows that oscillations due to electro-mechanical coupling can be generated spontaneously in smooth muscle cells. Such cellular dynamics are known as pacemaker dynamics. In this article, we address pacemaker dynamics associated with the interaction of [Formula: see text] and [Formula: see text] fluxes in the cell membrane of a smooth muscle cell. First we reduce a pacemaker model to a two-dimensional system equivalent to the reduced Morris-Lecar model and then perform a detailed numerical bifurcation analysis of the reduced model. Existing bifurcation analyses of the Morris-Lecar model concentrate on external applied current, whereas we focus on parameters that model the response of the cell to changes in transmural pressure. We reveal a transition between Type I and Type II excitabilities with no external current required. We also compute a two-parameter bifurcation diagram and show how the transition is explained by the bifurcation structure.
Collapse
Affiliation(s)
- H O Fatoyinbo
- School of Fundamental Sciences, Massey University, Palmerston North, New Zealand.
| | - R G Brown
- School of Fundamental Sciences, Massey University, Palmerston North, New Zealand
| | - D J W Simpson
- School of Fundamental Sciences, Massey University, Palmerston North, New Zealand
| | - B van Brunt
- School of Fundamental Sciences, Massey University, Palmerston North, New Zealand
| |
Collapse
|
10
|
Correction: Voltage-dependent inward currents in smooth muscle cells of skeletal muscle arterioles. PLoS One 2018; 13:e0203342. [PMID: 30153306 PMCID: PMC6112669 DOI: 10.1371/journal.pone.0203342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
|