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Wang H, Swore J, Sharma S, Szymanski JR, Yuste R, Daniel TL, Regnier M, Bosma MM, Fairhall AL. A complete biomechanical model of Hydra contractile behaviors, from neural drive to muscle to movement. Proc Natl Acad Sci U S A 2023; 120:e2210439120. [PMID: 36897982 PMCID: PMC10089167 DOI: 10.1073/pnas.2210439120] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 01/03/2023] [Indexed: 03/12/2023] Open
Abstract
How does neural activity drive muscles to produce behavior? The recent development of genetic lines in Hydra that allow complete calcium imaging of both neuronal and muscle activity, as well as systematic machine learning quantification of behaviors, makes this small cnidarian an ideal model system to understand and model the complete transformation from neural firing to body movements. To achieve this, we have built a neuromechanical model of Hydra's fluid-filled hydrostatic skeleton, showing how drive by neuronal activity activates distinct patterns of muscle activity and body column biomechanics. Our model is based on experimental measurements of neuronal and muscle activity and assumes gap junctional coupling among muscle cells and calcium-dependent force generation by muscles. With these assumptions, we can robustly reproduce a basic set of Hydra's behaviors. We can further explain puzzling experimental observations, including the dual timescale kinetics observed in muscle activation and the engagement of ectodermal and endodermal muscles in different behaviors. This work delineates the spatiotemporal control space of Hydra movement and can serve as a template for future efforts to systematically decipher the transformations in the neural basis of behavior.
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Affiliation(s)
- Hengji Wang
- Department of Physics, University of Washington, Seattle, WA98195
- Computational Neuroscience Center, University of Washington, Seattle, WA98195
| | - Joshua Swore
- Department of Biology, University of Washington, Seattle, WA98195
| | - Shashank Sharma
- Department of Physiology and Biophysics, University of Washington, Seattle, WA98195
| | - John R. Szymanski
- NeuroTechnology Center, Department of Biological Sciences, Columbia University, New York, NY10027
- Marine Biological Laboratory, Woods Hole, MA02543
| | - Rafael Yuste
- NeuroTechnology Center, Department of Biological Sciences, Columbia University, New York, NY10027
- Marine Biological Laboratory, Woods Hole, MA02543
| | - Thomas L. Daniel
- Department of Biology, University of Washington, Seattle, WA98195
| | - Michael Regnier
- Department of Bioengineering, University of Washington, Seattle, WA98195
| | - Martha M. Bosma
- Department of Biology, University of Washington, Seattle, WA98195
| | - Adrienne L. Fairhall
- Department of Physics, University of Washington, Seattle, WA98195
- Computational Neuroscience Center, University of Washington, Seattle, WA98195
- Department of Physiology and Biophysics, University of Washington, Seattle, WA98195
- Marine Biological Laboratory, Woods Hole, MA02543
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2
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Dowding S, Zakkaroff C, Moore S, David T. Coronary Smooth Muscle Cell Calcium Dynamics: Effects of Bifurcation Angle on Atheroprone Conditions. Front Physiol 2018; 9:1528. [PMID: 30429800 PMCID: PMC6220094 DOI: 10.3389/fphys.2018.01528] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 10/11/2018] [Indexed: 11/20/2022] Open
Abstract
This work investigates the effect of arterial bifurcation angulation on atherosclerosis development through in-silico simulations of coupled cell dynamics. The computational model presented here combines cellular pathways, fluid dynamics, and physiologically-realistic vessel geometries as observed in the human vasculature. The coupled cells model includes endothelial cells (ECs) and smooth muscle cells (SMCs) with ion dynamics, hetero and homotypic coupling, as well as electro-diffusive coupling. Three arterial bifurcation surface models were used in the coupled cells simulations. All three simulations showed propagating waves of Ca2+ in both the SMC and EC layers, following the introduction of a luminal agonist, in this case ATP. Immediately following the introduction of ATP concentration Ca2+ waves propagate from the area of high ATP toward the areas of low ATP concentration, forming complex patterns where waves interact with eachother, collide and fade. These dynamic phenomena are repeated with a series of waves of slower velocity. The underlying motivation of this research was to examine the macro-scale phenomena, given that the characteristic length scales of atherosclerotic plaques are much larger than a single cell. The micro-scale dynamics were modeled on macro-scale arterial bifurcation surfaces containing over one million cells. The results of the simulations presented here suggest that susceptibility to atherosclerosis development depends on the bifurcation angulation. In conjunction with findings reported in the literature, the simulation results demonstrate that arterial bifurcations containing wider angles have a more prominent influence on the coupled cells pathways associated with the development of atherosclerosis, by means of disturbed flow and lower SMC Ca2+ concentrations. The discussion of the results considers the findings of this research within the context of the potential link between information transport through frequency encoding of Ca2+ wave dynamics and development of atheroprone conditions.
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Affiliation(s)
- Stewart Dowding
- UC High Performance Computing Centre, University of Canterbury, Christchurch, New Zealand
| | - Constantine Zakkaroff
- Department of Accounting and Information Systems, University of Canterbury, Christchurch, New Zealand
| | | | - Tim David
- UC High Performance Computing Centre, University of Canterbury, Christchurch, New Zealand
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3
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AUX1-mediated root hair auxin influx governs SCF TIR1/AFB-type Ca 2+ signaling. Nat Commun 2018; 9:1174. [PMID: 29563504 PMCID: PMC5862985 DOI: 10.1038/s41467-018-03582-5] [Citation(s) in RCA: 120] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 02/26/2018] [Indexed: 01/01/2023] Open
Abstract
Auxin is a key regulator of plant growth and development, but the causal relationship between hormone transport and root responses remains unresolved. Here we describe auxin uptake, together with early steps in signaling, in Arabidopsis root hairs. Using intracellular microelectrodes we show membrane depolarization, in response to IAA in a concentration- and pH-dependent manner. This depolarization is strongly impaired in aux1 mutants, indicating that AUX1 is the major transporter for auxin uptake in root hairs. Local intracellular auxin application triggers Ca2+ signals that propagate as long-distance waves between root cells and modulate their auxin responses. AUX1-mediated IAA transport, as well as IAA- triggered calcium signals, are blocked by treatment with the SCFTIR1/AFB - inhibitor auxinole. Further, they are strongly reduced in the tir1afb2afb3 and the cngc14 mutant. Our study reveals that the AUX1 transporter, the SCFTIR1/AFB receptor and the CNGC14 Ca2+ channel, mediate fast auxin signaling in roots. Auxin regulates multiple aspects of plant growth and development. Here Dindas et al. show that in root-hair cells, the AUX1 auxin influx carrier mediates proton-driven auxin import that is perceived by auxin receptors and coupled to Ca2+ waves that may modulate adaptive responses in the root.
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Zakkaroff C, Moore S, Dowding S, David T. 3D time-varying simulations of Ca 2+ dynamics in arterial coupled cells: A massively parallel implementation. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2017; 33:e02786. [PMID: 27062231 PMCID: PMC5298049 DOI: 10.1002/cnm.2786] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 03/07/2016] [Accepted: 03/19/2016] [Indexed: 05/18/2023]
Abstract
Preferential locations of atherosclerotic plaque are strongly associated with the areas of low wall shear stress and disturbed haemodynamic characteristics such as flow detachment, flow recirculation and oscillatory flow. The areas of low wall shear stress are also associated with the reduced production of adenosine triphosphate in the endothelial layer, as well as the resulting reduced production of inositol trisphosphate (IP3 ). The subsequent variation in Ca2+ signalling and nitric oxide synthesis could lead to the impairment of the atheroprotective function played by nitric oxide. In previous studies, it has been suggested that the reduced IP3 and Ca2+ signalling can explain the correlation of atherosclerosis with induced low WSS and disturbed flow characteristics. The massively parallel implementation described in this article provides insight into the dynamics of coupled smooth muscle cells and endothelial cells mapped onto the surface of an idealised arterial bifurcation. We show that variations in coupling parameters, which model normal and pathological conditions, provide vastly different smooth muscle cell Ca2+ dynamics and wave propagation profiles. The extensibility of the coupled cells model and scalability of the implementation provide a solid framework for in silico investigations of the interaction between complex cellular chemistry and the macro-scale processes determined by fluid dynamics. © 2016 The Authors. International Journal for Numerical Methods in Biomedical Engineering published by John Wiley & Sons Ltd.
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Affiliation(s)
| | - Stephen Moore
- IBM Research Collaboratory for Life SciencesMelbourneAustralia
| | - Stewart Dowding
- UC HPC CentreUniversity of CanterburyChristchurchNew Zealand
| | - Tim David
- UC HPC CentreUniversity of CanterburyChristchurchNew Zealand
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5
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Bicen AO, Akyildiz IF, Balasubramaniam S, Koucheryavy Y. Linear Channel Modeling and Error Analysis for Intra/Inter-Cellular Ca 2+ Molecular Communication. IEEE Trans Nanobioscience 2016; 15:488-498. [PMID: 27514062 DOI: 10.1109/tnb.2016.2574639] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The use of intra/inter-cellular calcium ion (Ca2+) signaling for molecular communication (MC) is investigated in this paper. In particular, the elevation of the intracellular Ca2+ concentration upon the external excitation, i.e., Ca2+ wave generation, and the intercellular propagation of Ca2+ wave over consecutive cells are studied for information transmission. The main objective of this paper is to develop a linear channel model for intra/inter-cellular Ca2+ MC. In this context, the end-to-end Ca2+ MC system is studied under three blocks: the wave generation, the gap junctional (intercellular) propagation, and the intracellular propagation. The wave generation block captures the intracellular Ca2+ signaling pathway including the release of Ca2+ from the organelles and the buffers inside a cell, and the intake from the extracellular space. The gap junctional (intercellular) propagation block captures the Ca2+ transition through the gap junctions between the touching cells. The intracellular propagation block defines the effect of the cytoplasmic diffusion. Using the developed blocks for the different biophysical phenomena, the end-to-end channel gain and delay formulas are derived. Furthermore, the bit error probability is studied to reveal the impact of the detection threshold. This work provides the basis for the modeling, analysis and the design of Ca2+ MC systems.
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Quijano JC, Raynaud F, Nguyen D, Piacentini N, Meister JJ. Intercellular ultrafast Ca(2+) wave in vascular smooth muscle cells: numerical and experimental study. Sci Rep 2016; 6:31271. [PMID: 27507785 PMCID: PMC4978975 DOI: 10.1038/srep31271] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 07/06/2016] [Indexed: 01/08/2023] Open
Abstract
Vascular smooth muscle cells exhibit intercellular Ca2+ waves in response to local mechanical or KCl stimulation. Recently, a new type of intercellular Ca2+ wave was observed in vitro in a linear arrangement of smooth muscle cells. The intercellular wave was denominated ultrafast Ca2+ wave and it was suggested to be the result of the interplay between membrane potential and Ca2+ dynamics which depended on influx of extracellular Ca2+, cell membrane depolarization and its intercel- lular propagation. In the present study we measured experimentally the conduction velocity of the membrane depolarization and performed simulations of the ultrafast Ca2+ wave along coupled smooth muscle cells. Numerical results reproduced a wide spectrum of experimental observations, including Ca2+ wave velocity, electrotonic membrane depolarization along the network, effects of inhibitors and independence of the Ca2+ wave speed on the intracellular stores. The numerical data also provided new physiological insights suggesting ranges of crucial model parameters that may be altered experimentally and that could significantly affect wave kinetics allowing the modulation of the wave characteristics experimentally. Numerical and experimental results supported the hypothesis that the propagation of membrane depolarization acts as an intercellular messenger mediating intercellular ultrafast Ca2+ waves in smooth muscle cells.
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Affiliation(s)
- J C Quijano
- Laboratory of Cell Biophysics, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.,Facultad de Ciencias Básicas, Politécnico Colombiano JIC, Medellín, Colombia
| | - F Raynaud
- Laboratory of Cell Biophysics, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.,Computational Systems Oncology, Department of Computational Biology, University of Lausanne, Lausanne, Switzerland
| | - D Nguyen
- Laboratory of Cell Biophysics, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - N Piacentini
- Laboratory of Cell Biophysics, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - J J Meister
- Laboratory of Cell Biophysics, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
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7
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Ho IL, Moshkforoush A, Hong K, Meininger GA, Hill MA, Tsoukias NM, Kuo W. Inherent rhythm of smooth muscle cells in rat mesenteric arterioles: An eigensystem formulation. Phys Rev E 2016; 93:042415. [PMID: 27176337 DOI: 10.1103/physreve.93.042415] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Indexed: 11/07/2022]
Abstract
On the basis of experimental data and mathematical equations in the literature, we remodel the ionic dynamics of smooth muscle cells (SMCs) as an eigensystem formulation, which is valid for investigating finite variations of variables from the equilibrium such as in common experimental operations. This algorithm provides an alternate viewpoint from frequency-domain analysis and enables one to probe functionalities of SMCs' rhythm by means of a resonance-related mechanism. Numerical results show three types of calcium oscillations of SMCs in mesenteric arterioles: spontaneous calcium oscillation, agonist-dependent calcium oscillation, and agonist-dependent calcium spike. For simple single and double SMCs, we demonstrate properties of synchronization among complex signals related to calcium oscillations, and show different correlation relations between calcium and voltage signals for various synchronization and resonance conditions. For practical cell clusters, our analyses indicate that the rhythm of SMCs could (1) benefit enhancements of signal communications among remote cells, (2) respond to a significant calcium peaking against transient stimulations for triggering globally oscillating modes, and (3) characterize the globally oscillating modes via frog-leap (non-molecular-diffusion) calcium waves across inhomogeneous SMCs.
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Affiliation(s)
- I Lin Ho
- Department of Physics, National Chung Hsing University, Taichung 402, Taiwan, Republic of China.,Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri 65211, USA
| | - Arash Moshkforoush
- Department of Biomedical Engineering, Florida International University, 10555 West Flagler Street, EC 2674, Miami, Florida 33174, USA
| | - Kwangseok Hong
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri 65211, USA.,Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri 65211, USA
| | - Gerald A Meininger
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri 65211, USA.,Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri 65211, USA
| | - Michael A Hill
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri 65211, USA.,Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri 65211, USA
| | - Nikolaos M Tsoukias
- Department of Biomedical Engineering, Florida International University, 10555 West Flagler Street, EC 2674, Miami, Florida 33174, USA
| | - Watson Kuo
- Department of Physics, National Chung Hsing University, Taichung 402, Taiwan, Republic of China
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8
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Katow H. Mechanisms of the epithelial-to-mesenchymal transition in sea urchin embryos. Tissue Barriers 2015; 3:e1059004. [PMID: 26716069 PMCID: PMC4681286 DOI: 10.1080/21688370.2015.1059004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 05/25/2015] [Accepted: 05/29/2015] [Indexed: 12/30/2022] Open
Abstract
Sea urchin mesenchyme is composed of the large micromere-derived spiculogenetic primary mesenchyme cells (PMC), veg2-tier macromere-derived non-spiculogenetic mesenchyme cells, the small micromere-derived germ cells, and the macro- and mesomere-derived neuronal mesenchyme cells. They are formed through the epithelial-to-mesenchymal transition (EMT) and possess multipotency, except PMCs that solely differentiate larval spicules. The process of EMT is associated with modification of epithelial cell surface property that includes loss of affinity to the apical and basal extracellular matrices, inter-epithelial cell adherens junctions and epithelial cell surface-specific proteins. These cell surface structures and molecules are endocytosed during EMT and utilized as initiators of cytoplasmic signaling pathways that often initiate protein phosphorylation to activate the gene regulatory networks. Acquisition of cell motility after EMT in these mesenchyme cells is associated with the expression of proteins such as Lefty, Snail and Seawi. Structural simplicity and genomic database of this model will further promote detailed EMT research.
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Affiliation(s)
- Hideki Katow
- Research Center for Marine Biology; Tohoku University; Asamushi, Aomori, Japan
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9
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Quijano JC, Vianay B, Bény JL, Meister JJ. Ultrafast Ca2+ wave in cultured vascular smooth muscle cells aligned on a micropatterned surface. Cell Calcium 2013; 54:436-45. [PMID: 24183802 DOI: 10.1016/j.ceca.2013.10.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Revised: 10/08/2013] [Accepted: 10/09/2013] [Indexed: 11/29/2022]
Abstract
Communication between vascular smooth muscle cells (SMCs) allows control of their contraction and so regulation of blood flow. The contractile state of SMCs is regulated by cytosolic Ca2+ concentration ([Ca2+]i) which propagates as Ca2+ waves over a significant distance along the vessel. We have characterized an intercellular ultrafast Ca2+ wave observed in cultured A7r5 cell line and in primary cultured SMCs (pSMCs) from rat mesenteric arteries. This wave, induced by local mechanical or local KCl stimulation, had a velocity around 15 mm/s. Combining of precise alignment of cells with fast Ca2+ imaging and intracellular membrane potential recording, allowed us to analyze rapid [Ca2+]i dynamics and membrane potential events along the network of cells. The rate of [Ca2+]i increase along the network decreased with distance from the stimulation site. Gap junctions or voltage-operated Ca2+ channels (VOCCs) inhibition suppressed the ultrafast Ca2+ wave. Mechanical stimulation induced a membrane depolarization that propagated and that decayed exponentially with distance. Our results demonstrate that an electrotonic spread of membrane depolarization drives a rapid Ca2+ entry from the external medium through VOCCs, modeled as an ultrafast Ca2+ wave. This wave may trigger and drive slower Ca2+ waves observed ex vivo and in vivo.
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Affiliation(s)
- Jairo C Quijano
- Laboratory of Cell Biophysics, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland; Facultad de Ciencias Básicas, Politécnico Colombiano JIC, Medellín, Colombia.
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10
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Nagaraja S, Kapela A, Tsoukias NM. Intercellular communication in the vascular wall: a modeling perspective. Microcirculation 2012; 19:391-402. [PMID: 22340204 DOI: 10.1111/j.1549-8719.2012.00171.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Movement of ions (Ca(2+) , K(+) , Na(+) , and Cl(-) ) and second messenger molecules like inositol 1, 4, 5-trisphosphate inside and in between different cells is the basis of many signaling mechanisms in the microcirculation. In spite of the vast experimental efforts directed toward evaluation of these fluxes, it has been a challenge to establish their roles in many essential microcirculatory phenomena. Recently, detailed theoretical models of calcium dynamics and plasma membrane electrophysiology have emerged to assist in the quantification of these intra and intercellular fluxes and enhance understanding of their physiological importance. This perspective reviews selected models relevant to estimation of such intra and intercellular ionic and second messenger fluxes and prediction of their relative significance to a variety of vascular phenomena, such as myoendothelial feedback, conducted responses, and vasomotion.
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Affiliation(s)
- Sridevi Nagaraja
- Department of Biomedical Engineering, Florida International University, Miami, Florida 33174, USA
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11
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Abstract
Intercellular calcium (Ca(2+)) waves (ICWs) represent the propagation of increases in intracellular Ca(2+) through a syncytium of cells and appear to be a fundamental mechanism for coordinating multicellular responses. ICWs occur in a wide diversity of cells and have been extensively studied in vitro. More recent studies focus on ICWs in vivo. ICWs are triggered by a variety of stimuli and involve the release of Ca(2+) from internal stores. The propagation of ICWs predominately involves cell communication with internal messengers moving via gap junctions or extracellular messengers mediating paracrine signaling. ICWs appear to be important in both normal physiology as well as pathophysiological processes in a variety of organs and tissues including brain, liver, retina, cochlea, and vascular tissue. We review here the mechanisms of initiation and propagation of ICWs, the key intra- and extracellular messengers (inositol 1,4,5-trisphosphate and ATP) mediating ICWs, and the proposed physiological functions of ICWs.
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Affiliation(s)
- Luc Leybaert
- Department of Basic Medical Sciences, Physiology Group, Faculty of Medicine & Health Sciences, Ghent University, Ghent, Belgium.
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12
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A three-dimensional chemo-mechanical continuum model for smooth muscle contraction. J Mech Behav Biomed Mater 2012; 13:215-29. [PMID: 22926184 DOI: 10.1016/j.jmbbm.2012.05.015] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 05/21/2012] [Accepted: 05/23/2012] [Indexed: 11/22/2022]
Abstract
Based on two fields, namely the placement and the calcium concentration, a chemo-mechanically coupled three-dimensional model, describing the contractile behaviour of smooth muscles, is presented by means of a strain energy function. The strain energy function (Schmitz and Böl, 2011) is additively decomposed into a passive part, relating to elastin and collagen, and an active calcium-driven part related to the chemical contraction of the smooth muscle cells. For the description of the calcium phase the four state cross-bridge model of Hai and Murphy (Hai and Murphy, 1988) has been implemented into the finite element method. Beside three-dimensional illustrative boundary-value problems demonstrating the features of the presented modelling concept, simulations on an idealised artery document the applicability of the model to more realistic geometries.
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Buchner T, Pietkun J, Kuklik P. Complex activity patterns in arterial wall: results from a model of calcium dynamics. Comput Biol Med 2011; 42:267-75. [PMID: 22204868 DOI: 10.1016/j.compbiomed.2011.12.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Revised: 11/24/2011] [Accepted: 12/01/2011] [Indexed: 11/17/2022]
Abstract
Using a dynamical model of smooth muscle cells in an arterial wall, defined as a system of coupled five-dimensional nonlinear oscillators, on a grid with cylindrical symmetry, we compare the admissible activity patterns with those known from the heart tissue. We postulate on numerical basis the possibility to induce a stable spiral wave in the arterial wall. Such a spiral wave can inhibit the propagation of the axial calcium wave and effectively stop the vasomotion. We also discuss the dynamics of the circumferential calcium wave in comparison to rotors in venous ostia that are a common source of supraventricular ectopy. We show that the velocity and in consequence the frequency range of the circumferential calcium wave is by orders of magnitude too small compared to that of the rotors. The mechanism of the rotor is not likely to involve the calcium-related dynamics of the smooth muscle cells. The calcium-related dynamics which is voltage-independent and hard to be reset seems to actually protect the blood vessels against the electric activity of the atria. We also discuss the microreentry phenomenon, which was found in numerical experiments in the studied model.
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Affiliation(s)
- Teodor Buchner
- Physics of Complex Systems Division, Faculty of Physics, Warsaw University of Technology, ul Koszykowa 75, 00-662 Warsaw, Poland.
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14
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Halidi N, Boittin FX, Bény JL, Meister JJ. Propagation of fast and slow intercellular Ca2+ waves in primary cultured arterial smooth muscle cells. Cell Calcium 2011; 50:459-67. [DOI: 10.1016/j.ceca.2011.08.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2011] [Revised: 08/02/2011] [Accepted: 08/02/2011] [Indexed: 11/30/2022]
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