scholarly journals Thrombin Inhibits Intercellular Calcium Wave Propagation in Corneal Endothelial Cells by Modulation of Hemichannels and Gap Junctions

2007 ◽  
Vol 48 (1) ◽  
pp. 120 ◽  
Author(s):  
Catheleyne D’hondt ◽  
Raf Ponsaerts ◽  
Sangly P. Srinivas ◽  
Johan Vereecke ◽  
Bernard Himpens
Keyword(s):  
Endothelial Cells ◽  
Wave Propagation ◽  
Gap Junctions ◽  
Calcium Wave ◽  
Corneal Endothelial Cells

The Myosin II ATPase Inhibitor Blebbistatin Prevents Thrombin-Induced Inhibition of Intercellular Calcium Wave Propagation in Corneal Endothelial Cells

2008 ◽  
Vol 49 (11) ◽  
pp. 4816 ◽  
Author(s):  
Raf Ponsaerts ◽  
Catheleyne D'hondt ◽  
Geert Bultynck ◽  
Sangly P. Srinivas ◽  
Johan Vereecke ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Wave Propagation ◽  
Myosin Ii ◽  
Calcium Wave ◽  
Corneal Endothelial Cells ◽  
Atpase Inhibitor

A novel form of cellular communication among thymic epithelial cells: intercellular calcium wave propagation

2003 ◽  
Vol 285 (5) ◽  
pp. C1304-C1313 ◽  
Author(s):  
O. K. Nihei ◽  
A. C. Campos de Carvalho ◽  
D. C. Spray ◽  
W. Savino ◽  
L. A. Alves
Keyword(s):  
Wave Propagation ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Gap Junctions ◽  
Thymic Epithelial Cells ◽  
Calcium Wave ◽  
Thymic Epithelial Cell ◽  
Calcium Waves ◽  
Thymic Nurse Cells ◽  
Epithelial Cell Lines

We here describe intercellular calcium waves as a novel form of cellular communication among thymic epithelial cells. We first characterized the mechanical induction of intercellular calcium waves in different thymic epithelial cell preparations: cortical 1-4C18 and medullary 3-10 thymic epithelial cell lines and primary cultures of thymic “nurse” cells. All thymic epithelial preparations responded with intercellular calcium wave propagation after mechanical stimulation. In general, the propagation efficacy of intercellular calcium waves in these cells was high, reaching 80-100% of the cells within a given confocal microscopic field, with a mean velocity of 6-10 μm/s and mean amplitude of 1.4- to 1.7-fold the basal calcium level. As evaluated by heptanol and suramin treatment, our results suggest the participation of both gap junctions and P2 receptors in the propagation of intercellular calcium waves in thymic nurse cells and the more prominent participation of gap junctions in thymic epithelial cell lines. Finally, in cocultures, the transmission of intercellular calcium wave was not observed between the mechanically stimulated thymic epithelial cell and adherent thymocytes, suggesting that intercellular calcium wave propagation is limited to thymic epithelial cells and does not affect the neighboring thymocytes. In conclusion, these data describe for the first time intercellular calcium waves in thymic epithelial cells and the participation of both gap junctions and P2 receptors in their propagation.

scholarly journals Intercellular calcium wave propagation in linear and circuit-like bone cell networks

2010 ◽  
Vol 368 (1912) ◽  
pp. 617-633 ◽  
Author(s):  
Bo Huo ◽  
Xin L. Lu ◽  
X. Edward Guo
Keyword(s):  
Wave Propagation ◽  
Gap Junctions ◽  
Calcium Release ◽  
Bone Cells ◽  
Molecular Transport ◽  
Bone Cell ◽  
Calcium Wave ◽  
Contact Printing ◽  
Inhibition Studies ◽  
Cell Networks

In the present study, the mechanism of intercellular calcium wave propagation in bone cell networks was identified. By using micro-contact printing and self-assembled monolayer technologies, two types of in vitro bone cell networks were constructed: open-ended linear chains and looped hexagonal networks with precisely controlled intercellular distances. Intracellular calcium responses of the cells were recorded and analysed when a single cell in the network was mechanically stimulated by nano-indentation. The looped cell network was shown to be more efficient than the linear pattern in transferring calcium signals from cell to cell. This phenomenon was further examined by pathway-inhibition studies. Intercellular calcium wave propagation was significantly impeded when extracellular adenosine triphosphate (ATP) in the medium was hydrolysed. Chemical uncoupling of gap junctions, however, did not significantly decrease the transferred distance of the calcium wave in the cell networks. Thus, it is extracellular ATP diffusion, rather than molecular transport through gap junctions, that dominantly mediates the transmission of mechanically elicited intercellular calcium waves in bone cells. The inhibition studies also demonstrated that the mechanical stimulation-induced calcium responses required extracellular calcium influx, whereas the ATP-elicited calcium wave relied on calcium release from the calcium store of the endoplasmic reticulum.

scholarly journals Vesicular ATP Is the Predominant Cause of Intercellular Calcium Waves in Astrocytes

2007 ◽  
Vol 129 (6) ◽  
pp. 485-491 ◽  
Author(s):  
David N. Bowser ◽  
Baljit S. Khakh
Keyword(s):  
Wave Propagation ◽  
Gap Junctions ◽  
Glutamate Receptors ◽  
Extracellular Space ◽  
Metabotropic Glutamate Receptors ◽  
Calcium Wave ◽  
Calcium Waves ◽  
Metabotropic Glutamate ◽  
Spatiotemporal Scales ◽  
Hippocampal Astrocytes

Brain astrocytes signal to each other and neurons. They use changes in their intracellular calcium levels to trigger release of transmitters into the extracellular space. These can then activate receptors on other nearby astrocytes and trigger a propagated calcium wave that can travel several hundred micrometers over a timescale of seconds. A role for endogenous ATP in calcium wave propagation in hippocampal astrocytes has been suggested, but the mechanisms remain incompletely understood. Here we explored how calcium waves arise and directly tested whether endogenously released ATP contributes to astrocyte calcium wave propagation in hippocampal astrocytes. We find that vesicular ATP is the major, if not the sole, determinant of astrocyte calcium wave propagation over distances between ∼100 and 250 μm, and ∼15 s from the point of wave initiation. These actions of ATP are mediated by P2Y1 receptors. In contrast, metabotropic glutamate receptors and gap junctions do not contribute significantly to calcium wave propagation. Our data suggest that endogenous extracellular astrocytic ATP can signal over broad spatiotemporal scales.

scholarly journals Calcium Wave Propagation in Networks of Endothelial Cells: Model-based Theoretical and Experimental Study

2012 ◽  
Vol 8 (12) ◽  
pp. e1002847 ◽  
Author(s):  
Juexuan Long ◽  
Michael Junkin ◽  
Pak Kin Wong ◽  
James Hoying ◽  
Pierre Deymier
Keyword(s):  
Experimental Study ◽  
Endothelial Cells ◽  
Wave Propagation ◽  
Calcium Wave ◽  
Model Based

scholarly journals Connexin 40 and ATP-dependent intercellular calcium wave in renal glomerular endothelial cells

2008 ◽  
Vol 294 (6) ◽  
pp. R1769-R1776 ◽  
Author(s):  
Ildikó Toma ◽  
Eric Bansal ◽  
Elliott J. Meer ◽  
Jung Julie Kang ◽  
Sarah L. Vargas ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Wave Propagation ◽  
Fold Increase ◽  
Extracellular Atp ◽  
Physical Contact ◽  
Calcium Wave ◽  
Fluorescence Confocal Microscopy ◽  
Glomerular Endothelial Cells ◽  
Connexin 40 ◽  
Voltage Dependent

Endothelial intracellular calcium ([Ca2+]i) plays an important role in the function of the juxtaglomerular vasculature. The present studies aimed to identify the existence and molecular elements of an endothelial calcium wave in cultured glomerular endothelial cells (GENC). GENCs on glass coverslips were loaded with Fluo-4/Fura red, and ratiometric [Ca2+]iimaging was performed using fluorescence confocal microscopy. Mechanical stimulation of a single GENC caused a nine-fold increase in [Ca2+]i, which propagated from cell to cell throughout the monolayer (7.9 ± 0.3 μm/s) in a regenerative manner (without decrement of amplitude, kinetics, and speed) over distances >400 μm. Inhibition of voltage-dependent calcium channels with nifedipine had no effect on the above parameters, but the removal of extracellular calcium reduced Δ[Ca2+]iby 50%. Importantly, the gap junction uncoupler α-glycyrrhetinic acid or knockdown of connexin 40 (Cx40) by transfecting GENCs with Cx40 short interfering RNA (siRNA) almost completely eliminated Δ[Ca2+]iand the calcium wave. Breakdown of extracellular ATP using a scavenger cocktail (apyrase and hexokinase) or nonselective inhibition of purinergic P2 receptors with suramin, had similar blocking effects. Scraping cells off along a line eliminated physical contact between cells but did not effect calcium wave propagation. Using an ATP biosensor technique, we detected a significant elevation in extracellular ATP (Δ = 76 ± 2 μM) during calcium wave propagation, which was abolished by Cx40 siRNA treatment (Δ = 6 ± 1 μM). These studies suggest that connexin 40 hemichannels and extracellular ATP are key molecular elements of the glomerular endothelial calcium wave, which may serve important juxtaglomerular functions.

Sign in / Sign up

Export Citation Format

Share Document