Annals of Biomedical Engineering

, Volume 29, Issue 8, pp 648–656 | Cite as

Electrical Impedance of Cultured Endothelium Under Fluid Flow

  • Natacha DePaola
  • Jeffrey E. Phelps
  • Lucio Florez
  • Charles R. Keese
  • Fred L. Minnear
  • Ivar Giaever
  • Peter Vincent


The morphological and functional status of organs, tissues, and cells can be assessed by evaluating their electrical impedance. Fluid shear stress regulates the morphology and function of endothelial cells in vitro. In this study, an electrical biosensor was used to investigate the dynamics of flow-induced alterations in endothelial cell morphology in vitro. Quantitative, real-time changes in the electrical impedance of endothelial monolayers were evaluated using a modified electric cell-substrate impedance sensing (ECIS) system. This ECIS/Flow system allows for a continuous evaluation of the cell monolayer impedance upon exposure to physiological fluid shear stress forces. Bovine aortic endothelial cells grown to confluence on thin film gold electrodes were exposed to fluid shear stress of 10 dynes/cm2 for a single uninterrupted 5 h time period or for two consecutive 30 min time periods separated by a 2 h no-flow interval. At the onset of flow, the monolayer electrical resistance sharply increased reaching 1.2 to 1.3 times the baseline in about 15 min followed by a sustained decrease in resistance to 1.1 and 0.85 times the baseline value after 30 min and 5 h of flow, respectively. The capacitance decreased at the onset of flow, started to recover after 15 min and after slightly overshooting the baseline values, decreased again with a prolonged exposure to flow. Measured changes in capacitance were in the order of 5% of the baseline values. The observed changes in endothelial impedance were reversible upon flow removal with a recovery rate that varied with the duration of the preceding flow exposure. These results demonstrate that the impedance of endothelial monolayers changes dynamically with flow indicating morphological and/or functional changes in the cell layer. This in vitro model system (ECIS/Flow) may be a very useful tool in the quantitative evaluation of flow-induced dynamic changes in cultured cells when used in conjunction with biological or biochemical assays able to determine the nature and mechanisms of the observed changes. © 2001 Biomedical Engineering Society.

PAC01: 8719Nn, 8719Uv, 8717-d

Endothelial cells Electrical impedance Shear stress Flow 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Barbee, K. A., P. F. Davies, and R. Lal. Shear stress-induced reorganization of the surface topography of living endothelial cells imaged by atomic force microscopy. Circ. Res.74:163–171, 1994.Google Scholar
  2. 2.
    Cooper, J., P. J. Del Vecchio, F. Minnear, K. Burhop, W. Selig, J. G. Garcia, and A. B. Malik. Measurement of albumin permeability across endothelial monolayers in vitro. J. Appl. Physiol.62:1076–1083, 1987.Google Scholar
  3. 3.
    Davies, P. F.How do vascular endothelial cells respond to flow?News Physiol. Sci.4:22–26, 1989.Google Scholar
  4. 4.
    Davies, P. F., K. A. Barbee, M. V. Volin, A. Robotewskyj, J. Chen, L. Joshep, M. L. Griem, M. N. Wernick, E. Jacobs, D. C. Polacek, N. DePaola, and A. I. Barakat. Spatial relationships in early signaling events of low-mediated endothelial mechanotransduction. Annu. Rev. Physiol.59:527–549, 1997.Google Scholar
  5. 5.
    Davies, P. F., A. Robotewskyj, and M. Griem. Quantitative studies of endothelial cell adhesion. J. Clin. Invest.93:2031–2038, 1994.Google Scholar
  6. 6.
    Davies, P. F., and S. C. Tripathi. Mechanical stress mechanisms and the cell: An endothelial paradigm. Circ. Res.72:239–245, 1993.Google Scholar
  7. 7.
    Davies, P. F., C. F. Dewey, S. R. Bussolari, E. J. Gordon, and M. A. Gimbrone. Influence of hemodynamic forces on vascular endothelial function: In vitro studies of shear stress and pinocytosis in bovine aortic cells. J. Clin. Invest.73:1121–1129, 1983.Google Scholar
  8. 8.
    DePaola, N., P. F. Davies, W. F. Pritchard, L. Florez, N. Harbeck, and D. C. Polacek. Spatial and temporal regulation of gap junction connexin43 in vascular endothelial cells exposed to controlled disturbed flows in vitro. Proc. Natl. Acad. Sci. U.S.A.96:3154–3159, 1999.Google Scholar
  9. 9.
    DePaola, N., M. A. Gimbrone, P. F. Davies, and C. F. Dewey. Vascular endothelium responds to fluid shear stress gradients. Arterioscler. Thromb.12:1254–1257, 1992; 13:465, 1993.Google Scholar
  10. 10.
    Dewey, C. F., S. R. Bussolari, M. A. Gimbrone, and P. F. Davies. The dynamic response of endothelial cells to fluid shear stress. J. Biomech. Eng.103:177–188, 1981.Google Scholar
  11. 11.
    Dull, R. O., and P. F. Davies. Flow modulation of agonist ATP response Ca++ coupling in vascular endothelial cells. Am. J. Physiol.261:H149–H151, 1991.Google Scholar
  12. 12.
    Frangos, J. A., S. G. Eskin, L. V. McIntire, and C. L. Ives. Flow effects on prostacyclin production by cultured human endothelial cells. Science227:1477–1479, 1985.Google Scholar
  13. 13.
    Franke, R. P., M. Grafe, H. Schnittler, D. Seiffge, C. Mittermayer, and D. Drenckhahn. Induction of human vascular endothelial stress fibers by fluid shear stress. Nature (London)307:648–649, 1984.Google Scholar
  14. 14.
    Garcia, J. G., K. Schaphorst, S. Shi, A. Vernin, C. M. Hart, K. Callahan, and C. Patterson. Mechanisms of ionomycin-induced endothelial cell barrier dysfunction. Am. J. Physiol.273:L172–L184, 1997.Google Scholar
  15. 15.
    Geiger, R. V., B. C. Berk, R. W. Alexander, and R. M. Nerem. Flow-induced calcium transient in single endothelial cell: Spatial and temporal analysis. Am. J. Physiol.262:C1411–C1417, 1992.Google Scholar
  16. 16.
    Ghosh, P. M., C. R. Keese, and I. Giaever. Morphological response of mammalian cells to pulsed ac fields. Bioelectrochem. Bioenerg.33:121–133, 1994.Google Scholar
  17. 17.
    Ghosh, P. M., C. R. Keese, and I. Giaever. Monitoring electropermeabilization in the plasma membrane of adherent mammalian cells. Biophys. J.64:1602–1609, 1993.Google Scholar
  18. 18.
    Giaever, I., and C. R. Keese. Micromotion of mammalian cells measured electrically. Proc. Natl. Acad. Sci. U.S.A.88:7896–7900, 1991; 90:1634, 1993.Google Scholar
  19. 19.
    Giaever, I., and C. R. Keese. Use of electrical fields to monitor the dynamical aspect of cell behavior in tissue culture. IEEE Trans. Biomed. Eng.33:242–247, 1986.Google Scholar
  20. 20.
    Giaever, I., and C. R. Keese. Monitoring fibroblast behavior in tissue culture with an applied electric field. Proc. Natl. Acad. Sci. U.S.A.81:3761–3764, 1984.Google Scholar
  21. 21.
    Gimbrone, M. A. Culture of vascular endothelium. In: Progress in Hemostasis and Thrombosis. New York: Grune and Stratton, 1976, pp. 1–28.Google Scholar
  22. 22.
    Jo, H., R. Dull, T. Hollis, and J. Tarbell. Endothelial albumin permeability is shear dependent, time dependent, and reversible. Am. J. Physiol.260:H1992–1996, 1991.Google Scholar
  23. 23.
    Levesque, M. J., and R. M. Nerem. Elongation and orientation of endothelial cell shape in response to shear. J. Biomech. Eng.107:341–347, 1985.Google Scholar
  24. 24.
    Morigi, M., C. Zoja, M. Figliuzzi, M. Foppolo, G. Micheletti, M. Bontempelli, M. Saroni, G. Remuzzi, and A. Remuzzi. Fluid shear stress modulates surface expression of adhesion molecules by endothelial cells. Blood85:1696–1703, 1995.Google Scholar
  25. 25.
    Nollert, M. U., and L. V. McIntere. Convective mass transfer effects on the intracellular calcium response of endothelial cells. J. Biomech. Eng.44:321–326, 1992.Google Scholar
  26. 26.
    Olesen, S. P., D. E. Clapham, and P. F. Davies. Hemodynamic Shear Stress Activates a K+ Current in Vascular Endothelial Cells. Boca Raton, Fla: CRC Press, 1988, pp. 123–139.Google Scholar
  27. 27.
    Resnick, N., T. Collins, W. Atkinson, D. T. Bonthron, C. F. Dewey, and M. A. Gimbrone. Platelet-derived growth factor B chain promoter contains a cis-acting fluid shear stress-responsive element. Proc. Natl. Acad. Sci. U.S.A.90:4591–4595, 1993.Google Scholar
  28. 28.
    Robotewskyj, A., R. O. Dull, M. L. Griem, and P. F. Davies. Dynamics of focal adhesion site remodelling in living endothelial cells in response to shear stress forces using confocal image analysis. FASEB J.5:A527, 1991.Google Scholar
  29. 29.
    Sampath, R., G. L. Kukielka, C. W. Smith, S. G. Eskin, and L. V. McIntire. Shear stress-mediated changes in the expression of leukocyte adhesion receptors on human umbilical vein endothelial cells in vitro. Ann. Biomed. Eng.23:247–256, 1995.Google Scholar
  30. 30.
    Sato, M., M. J. Levesque, and R. M. Nerem. Micropipette aspiration of cultured bovine aortic endothelial cells exposed to shear stress. Arteriosclerosis (Dallas)7:276–286, 1987.Google Scholar
  31. 31.
    Shen, J., F. Luscinskas, A. Connolly, C. F. Dewey, and M. A. Gimbrone. Fluid shear stress modulates cytosolic free calcium in vascular endothelial cells. Am. J. Physiol.262:C384–C390, 1992.Google Scholar
  32. 32.
    Sill, H., Y. Chang, J. Artman, J. Frangos, T. Hollis, and J. Tarbell. Shear stress increases hydraulic conductivity of cultured endothelial monolayers. Am. J. Physiol.268:H535–H543, 1995.Google Scholar
  33. 33.
    Tardy, Y., N. Resnick, T. Nagel, M. Gimbrone, and C. Dewey. Shear stress gradient remodel endothelial monolayers in vitro via a cell proliferation migration-loss cycle. Arterioscler. Thromb.17:3102–3106, 1997.Google Scholar
  34. 34.
    Tiruppathi, C., A. B. Malik, P. J. Del Vecchio, C. R. Keese, and I. Giaever. Electrical method for detection of endothelial cell shape change in real time: Assessment of endothelial barrier function. Proc. Natl. Acad. Sci. U.S.A.89:7919–7923, 1992.Google Scholar
  35. 35.
    Turner, M. R. Flows of liquids and electrical current through monolayers of cultured bovine arterial endothelium. J. Physiol. (London)449:1–20, 1992.Google Scholar
  36. 36.
    Varner, S. E., M. Russell, R. Medford, W. Alexander, and R. M. Nerem. Chronic laminar shear stress differentially inhibits inflammatory activation of vascular endothelial VCAM-1 and NF-kB. ASME Bioeng. Div. Publ. BED (NY)35:545–546, 1997.Google Scholar

Copyright information

© Biomedical Engineering Society 2001

Authors and Affiliations

  • Natacha DePaola
    • 1
  • Jeffrey E. Phelps
    • 1
  • Lucio Florez
    • 1
  • Charles R. Keese
    • 2
  • Fred L. Minnear
    • 3
  • Ivar Giaever
    • 4
  • Peter Vincent
    • 3
  1. 1.Department of Biomedical EngineeringRensselaer Polytechnic InstituteTroy
  2. 2.Department of BiologyRensselaer Polytechnic InstituteTroy
  3. 3.Center for Cardiovascular SciencesAlbany Medical CollegeAlbany
  4. 4.Department of PhysicsRensselaer Polytechnic InstituteTroy

Personalised recommendations