title: The effects of Ni(2+) on electrical signaling of Nitellopsis obtusa cells.
abstract: The effect of nickel (Ni) on the generation of plant bioelectrical signals was evaluated in Nitellopsis obtusa, a Characean model organism. Conventional glass-microelectrode technique and K(+)-anaesthesia method in current-clamp and voltage-clamp modes were used for the measurement and analysis of electrical parameters. Ni(2+) treatment rapidly influenced the action potential (AP) parameters namely, excitation threshold, AP peak and duration, membrane potential at various voltages and dynamics of ion currents. We conclude that altered electrical signaling pathway in the test organism constituted the early target for Ni toxicity imposition. The observed Ni interference could be ascribed to disturbed [Ca(2+)]cyt content, impaired Cl(-) and K(+) channels activity resulting in decreased excitability and repolarization rate in generated AP.
authors.affiliation: Department of Neurobiology and Biophysics, Faculty of Natural Science, Vilnius University, M. K. Ciurlionio 21/27, 03101, Vilnius, Lithuania. vilma.kisnieriene@gf.vu.lt.
authors.forename: Vilma
authors.initials: V
authors.lastname: Kisnieriene
authors.affiliation: Department of Neurobiology and Biophysics, Faculty of Natural Science, Vilnius University, M. K. Ciurlionio 21/27, 03101, Vilnius, Lithuania.
authors.forename: Indre
authors.initials: I
authors.lastname: Lapeikaite
authors.affiliation: Department of Neurobiology and Biophysics, Faculty of Natural Science, Vilnius University, M. K. Ciurlionio 21/27, 03101, Vilnius, Lithuania.
authors.forename: Olga
authors.initials: O
authors.lastname: Sevriukova
authors.affiliation: Department of Neurobiology and Biophysics, Faculty of Natural Science, Vilnius University, M. K. Ciurlionio 21/27, 03101, Vilnius, Lithuania.
authors.forename: Osvaldas
authors.initials: O
authors.lastname: Ruksenas
mesh_terms: D000200:Action Potentials / Q000187:drug effects / Q000528:radiation effects; D044522:Characeae / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D002712:Chlorides / Q000378:metabolism; D055724:Electrophysiological Phenomena / Q000187:drug effects* / Q000528:radiation effects; D008027:Light; D009532:Nickel / Q000494:pharmacology*; D017494:Proton Pumps / Q000378:metabolism; D012996:Solutions
chemical_list: D002712:Chlorides; D017494:Proton Pumps; D012996:Solutions; D009532:Nickel
keywords: Characeae; Membrane ion transport systems; Nickel toxicity; Plant electrical signaling