A non-linear voltage dependent charge movement in frog skeletal muscle.
1. Voltage-clamp experiments were carried out using the three microelectrode technique. Using this method membrane current density at V1 is proportional to deltaV( = V2 - V1) where V1 and V2 are voltages at distances 1 and 21 from the end of a fibre. Voltage dependent sodium currents were blocked by tetrodotoxin, potassium by tetraethylammonium ions and rubidium. Contraction was blocked by adding sucrose, 467 mM. 2. The current deltaV (control) associated with a positive voltage step from a hyperpolarized conditioning voltage to the holding potential, -80 mV, showed two components, a capacitative transient which decayed rapidly and a maintained steady level...
D000818:Animals; D001001:Anura; D004553:Electric Conductivity; D004594:Electrophysiology; D066298:In Vitro Techniques; D007700:Kinetics; D008433:Mathematics; D008564:Membrane Potentials / Q000187:drug effects; D008839:Microelectrodes; D009119:Muscle Contraction; D009132:Muscles / Q000187:drug effects / Q000502:physiology*; D011188:Potassium / Q000502:physiology; D011896:Rana temporaria; D012413:Rubidium / Q000494:pharmacology; D012519:Sarcoplasmic Reticulum / Q000502:physiology; D012964:Sodium / Q000502:physiology; D013757:Tetraethylammonium Compounds / Q000494:pharmacology; D013779:Tetrodotoxin / Q000494:pharmacology; D013997:Time Factors
D013757:Tetraethylammonium Compounds; D013779:Tetrodotoxin; D012964:Sodium; D012413:Rubidium; D011188:Potassium