Voltage clamp of bull-frog cardiac pace-maker cells: a quantitative analysis of potassium currents.
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چکیده
منابع مشابه
Calcium currents in GH3 cultured pituitary cells under whole-cell voltage-clamp: inhibition by voltage-dependent potassium currents.
To isolate inward Ca2+ currents in GH3 rat pituitary cells, an inward Na+ current as well as two outward K+ currents, a transient voltage-dependent current (IKV) and a slowly rising Ca2+-activated current (IKCa), must be suppressed. Blockage of these outward currents, usually achieved by replacement of intracellular K+ with Cs+, reveals sustained inward currents. Selective blockage of either K+...
متن کاملPharmacological analysis of voltage-dependent potassium currents in cultured skeletal myocytes of the frog Rana temporaria.
Previously, the existence of nine types of outward potassium current (IK) was shown. The whole family of IK may be divided into two groups: fast transient currents (f) with time to peak less than 70 ms (at test potential near 0 mV), and slow (s) components (Lukyanenko et al. 1993). The latter were completely blocked by 4-aminopyridine (4-AP) and the former were more sensitive to TEA than slow I...
متن کاملVoltage clamp analysis of membrane currents in larval muscle fibers of Drosophila: alteration of potassium currents in Shaker mutants.
The body wall muscles in Drosophila larvae are suitable for voltage clamp analysis of changes in membrane excitability caused by mutations. Both inward and outward ionic currents are present in these muscle fibers. The inward current is mediated by voltage-dependent Ca2+ channels. In Ca2+-free saline, the inward current is eliminated. The remaining outward K+ currents consist of two distinct co...
متن کاملVoltage Clamp Analysis of Repetitive Firing in Frog Atrial Trabeculae
The membrane currents responsible for induced pace-maker activity in frog atrial muscle were investigated using a double sucrose gap technique. The trabecula was clamped to the potential from which pace-making started (35—40 mV positive to resting potential) and immediately after that a test pulse was applied and the membrane inward current was measured. When the duration of the conditioning pu...
متن کاملAnalysis of cardiac pacemaker potential using a "voltage clamp" technique.
VASSALEE, MARIO. Analysis of card& pacemaker potential using a %ltage clamf3 technique. Am. J. Physiol. 210(6): 1335-1341. I g66.-Diastolic depolarization was studied by means of ccvoItage clamp” technique in short mammalian Purkinje fibers. Clamping the membrane potential at the maximal diastolic value resulted in an inward current rising with a time constant of 3 set in 5.4 mM K, indicating t...
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ژورنال
عنوان ژورنال: The Journal of Physiology
سال: 1985
ISSN: 0022-3751
DOI: 10.1113/jphysiol.1985.sp015857