Intracellular magnesium blocks sodium outward currents in a voltage- and dose-dependent manner.
Tail currents through Na+ channels have been measured in inside-out patches from Xenopus laevis oocytes injected with cDNA-derived mRNA coding for the rat brain type II Na+ channel. It is shown that intracellular Mg2+ blocks outward currents in a voltage- and dose-dependent manner with a half blocking concentration between 3 and 4 mM at 0 mV and a voltage dependence of e-fold per 49 mV.
Pusch
M
M
Max-Planck-Institut für biophysikalische Chemie, Göttingen, Federal Republic of Germany.
Conti
F
F
Stühmer
W
W
D000818:Animals; D001921:Brain / Q000378:metabolism; D004247:DNA / Q000235:genetics; D005260:Female; D006023:Glycoproteins / Q000235:genetics; D066298:In Vitro Techniques; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology / Q000502:physiology*; D008564:Membrane Potentials; D009865:Oocytes / Q000502:physiology*; D051381:Rats; D015222:Sodium Channels / Q000187:drug effects / Q000502:physiology*; D014982:Xenopus laevis
D006023:Glycoproteins; D015222:Sodium Channels; D004247:DNA; D008274:Magnesium