title: Altered excitability of cultured chromaffin cells following exposure to multi-walled carbon nanotubes.
abstract: We studied the effects of multi-walled carbon nanotubes (MWCNTs) on the electrophysiological properties of cultured mouse chromaffin cells, a model of spontaneously firing cells. The exposure of chromaffin cells to MWCNTs at increasing concentrations (30-263 μg/ml) for 24 h reduced, in a dose-dependent way, both the cell membrane input resistance and the number of spontaneously active cells (from 80-52%). Active cells that survived from the toxic effects of MWCNTs exhibited more positive resting potentials, higher firing frequencies and unaltered voltage-gated Ca(2+), Na(+) and K+ current amplitudes. MWCNTs slowed down the inactivation kinetics of Ca(2+)-dependent BK channels. These electrophysiological effects were accompanied by MWCNTs internalization, as confirmed by transmission electron microscopy, indicating that most of the toxic effects derive from a dose-dependent MWCNTs-cell interaction that damages the spontaneous cell activity.
authors.affiliation: Department of Neuroscience, University of Torino, Torino.
authors.forename: Daniela
authors.initials: D
authors.lastname: Gavello
authors.forename: David H F
authors.initials: DH
authors.lastname: Vandael
authors.forename: Roberta
authors.initials: R
authors.lastname: Cesa
authors.forename: Federica
authors.initials: F
authors.lastname: Premoselli
authors.forename: Andrea
authors.initials: A
authors.lastname: Marcantoni
authors.forename: Federico
authors.initials: F
authors.lastname: Cesano
authors.forename: Domenica
authors.initials: D
authors.lastname: Scarano
authors.forename: Bice
authors.initials: B
authors.lastname: Fubini
authors.forename: Emilio
authors.initials: E
authors.lastname: Carbone
authors.forename: Ivana
authors.initials: I
authors.lastname: Fenoglio
authors.forename: Valentina
authors.initials: V
authors.lastname: Carabelli
mesh_terms: D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D015220:Calcium Channels / Q000187:drug effects / Q000378:metabolism; D002452:Cell Count; D002462:Cell Membrane; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D019439:Chromaffin Cells / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D004305:Dose-Response Relationship, Drug; D004594:Electrophysiology; D007473:Ion Channels / Q000187:drug effects* / Q000378:metabolism; D051036:Large-Conductance Calcium-Activated Potassium Channels / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D037742:Nanotubes, Carbon / Q000633:toxicity*; D018408:Patch-Clamp Techniques; D024642:Potassium Channels, Voltage-Gated / Q000187:drug effects / Q000378:metabolism
chemical_list: D015220:Calcium Channels; D007473:Ion Channels; D051036:Large-Conductance Calcium-Activated Potassium Channels; D037742:Nanotubes, Carbon; D024642:Potassium Channels, Voltage-Gated