Pflügers Archiv

, Volume 439, Issue 3, pp 297–303

Volume dynamics in migrating epithelial cells measured with atomic force microscopy

  • S. W. Schneider
  • P. Pagel
  • C. Rotsch
  • T. Danker
  • H. Oberleithner
  • M. Radmacher
  • A. Schwab
Original Article

DOI: 10.1007/s004249900176

Cite this article as:
Schneider, S., Pagel, P., Rotsch, C. et al. Pflügers Arch – Eur J Physiol (2000) 439: 297. doi:10.1007/s004249900176

Abstract

Migration of transformed renal epithelial cells (transformed Madin-Darby canine kidney cells, MDCK-F cells) relies on the activity of a Ca2+-sensitive K+ channel (IK channel) that is more active at the rear end of these cells. We have postulated that intermittent IK channel activity induces local cell shrinkage at the rear end of migrating MDCK-F cells and thereby supports the cytoskeletal mechanisms of migration. However, due to the complex morphology of MDCK-F cells we have not yet been able to measure volume changes directly. The aim of the present study was to devise a new technique employing atomic force microscopy (AFM) to measure the volume of MDCK-F cells in their physiological environment and to demonstrate its dependence on IK channel activity. The spatial (x, y and z) co-ordinates of each pixel of the three-dimensional image of MDCK-F cells allow calculation of the volume of the column "underneath" a given pixel. Thus, total cell volume is the sum of all pixel-defined columns. The mean volume of 17 MDCK-F cells was 2500±300 fl. Blockade of the IK channel with the specific inhibitor charybdotoxin (CTX) increased cell volume by 17±4%; activation of IK by elevating the intracellular [Ca2+] with the Ca2+ ionophore ionomycin decreased cell volume by 19±3%. Subtraction images (experimental minus control) reveal that swelling and shrinkage occur predominantly at the rear end of MDCK-F cells. In summary, our experiments show that AFM allows the measurement not only of total cell volume of living cells in their physiological environment but also the tracing of local effects induced by the polarized distribution of K+ channel activity.

Atomic force microscope Elasticity IK channel Polarization Migration 

Copyright information

© Springer-Verlag 2000

Authors and Affiliations

  • S. W. Schneider
    • 1
  • P. Pagel
    • 1
  • C. Rotsch
    • 2
  • T. Danker
    • 1
  • H. Oberleithner
    • 1
  • M. Radmacher
    • 2
  • A. Schwab
    • 3
  1. 1.Physiologisches Institut, Robert-Koch-Strasse 27a, D-49148 MünsterGermany
  2. 2.Lehrstuhl für Angewandte Physik, Amalienstrasse 54, D-80799 MünchenGermany
  3. 3.Physiologisches Institut, Röntgenring 9, D-97070 WürzburgGermany