Slow calcium and potassium currents across frog muscle membrane: measurements with a vaseline-gap technique.
نویسندگان
چکیده
منابع مشابه
Evidence for voltage-dependent inactivation of slow currents through calcium channels in frog muscle membrane.
Two mechanisms of inactivation of slow inward current through calcium channels in frog skeletal muscle have been described: voltage dependent inactivation similar to that of classical sodium channels (Cota et al. 1982, 1984; Stanfield 1977); and calcium ions depletion inside the T-tubules as a result of inward current flowing through the T-membrane. In the latter case the inactivation is curren...
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Calcium currents in crayfish muscle fibres were studied by means of the vaseline gap voltage clamp technique. Overlapping potassium currents were fully suppressed using fibre fragments equilibrated in K+-free intracellular solution. The design of the recording chamber tailored to crayfish muscle fibres is described in detail. Ca currents recorded has a two-component time course. The transient (...
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In experiments on cut muscle fibers mounted in a double Vaseline-gap chamber, electrical measurements are usually made by measuring the voltage V1(t) in one end pool and by passing current I2(t) from the other end pool to the central pool, which is usually clamped to earth potential. The voltage in the current-passing end pool is denoted by V2(t). This article describes how the value of the hol...
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The kinetics of potassium tail currents have been studied in the omohyoid muscle of the rat using the three-microelectrode voltage-clamp technique. The currents were elicited by a two-pulse protocol in which a conditioning pulse to open channels was followed by a test step to varying levels. The tail currents reversed at a single well-defined potential (VK). At hyperpolarized test potentials (-...
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The understanding of neurotransmitter release at vertebrate synapses has been hampered by the paucity of preparations in which presynaptic ionic currents and postsynaptic responses can be monitored directly. We used cultured embryonic Xenopus neuromuscular junctions and simultaneous pre- and postsynaptic patch-clamp current-recording procedures to identify the major presynaptic conductances und...
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ژورنال
عنوان ژورنال: The Journal of Physiology
سال: 1981
ISSN: 0022-3751
DOI: 10.1113/jphysiol.1981.sp013622