title: Reversible and irreversible rotating field-induced membrane modifications.
abstract: We analyse the charge distribution as submitted by additionally induced transmembrane potentials in rotating electric fields. In contrast to d.c. and a.c. fields, in rotating fields the induced peak potential differences across the membrane systems are phase shifted with respect both to each other and to the external field vector. These phase differences are strongly frequency-dependent but were also influenced by the electrical properties of both the cell and the surrounding medium. We extend our investigation up to the non-linear field strength range of electrorotation and found reversible and irreversible changes in the rotational behavior of several cells. The most convenient variables for describing non-linear electrorotation are the characteristic frequency (fc1) and the corresponding angular velocity (omega c) of the cells. With increasing field strength the observed rotational behavior becomes more and more irreversible and finally rupture of the membrane occurs.
authors.affiliation: Department of Biology, Humboldt University of Berlin, G.D.R.
authors.forename: G
authors.initials: G
authors.lastname: Fuhr
authors.forename: T
authors.initials: T
authors.lastname: Müller
authors.forename: R
authors.initials: R
authors.lastname: Hagedorn
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000502:physiology*; D002736:Chloroplasts / Q000648:ultrastructure; D004553:Electric Conductivity; D004560:Electricity; D005260:Female; D007425:Intracellular Membranes / Q000502:physiology; D008564:Membrane Potentials; D051379:Mice; D009865:Oocytes / Q000648:ultrastructure; D010944:Plants / Q000648:ultrastructure; D011523:Protoplasts / Q000648:ultrastructure; D012399:Rotation