Gating of the expressed Cav3.1 calcium channel.
Intramembrane charge movement originating from Cav3.1 (T-type) channel expressed in HEK 293 cells was investigated. Ion current was blocked by 1 mM La3+. Charge movement was detectable for depolarizations above approximately -70 mV and saturated above +60 mV. The voltage dependence of charge movement followed a single Boltzmann function with half-maximal activation voltage +12.9 mV and +12.3 mV and with slopes of 22.4 mV and 18.1 mV for the ON- and OFF-charge movement, respectively. Inactivation of I(Ca) by prolonged depolarization pulse did not immobilize intramembrane charge movement in the Cav3.1 channel.
Lacinová
L'
L
Institute of Molecular Physiology and Genetics, Slovak Academy of Sciences, Bratislava, Slovak Republic. umfglaci@kramare.savba.sk
Klugbauer
N
N
Hofmann
F
F
D002118:Calcium / Q000378:metabolism; D015220:Calcium Channels / Q000502:physiology; D020747:Calcium Channels, T-Type / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D002460:Cell Line; D004553:Electric Conductivity; D006801:Humans; D015640:Ion Channel Gating; D017136:Ion Transport; D007700:Kinetics; D014162:Transfection
D015220:Calcium Channels; D020747:Calcium Channels, T-Type; D002118:Calcium