Abstract
Single anion-selective channels were studied in excised membrane patches of adult frog toe muscle. The conductance γ and the probabilityp o of the main open state were determined for various ionic compositions of the extra-and intracellular solutions. γ=280 pS in symmetrical 110 mM NaCl, pH 7.4 solutions at 15°C. Higher γ values were found at elevated internal or external NaCl concentrations, in 70 mM external CaCl2 and at lower extracellular pH. Thep o(E) curve declined steeply with hyperpolarization and was shifted towards more negative potentials at increased internal ionic strength and at higher external pH. Positive shifts were induced by extracellular Ca. The results show that the anion channel saturates at Cl concentrations >110 mM, that the potential profile of an open channel is almost symmetrical and that channel gating is affected by neighboring channels. It is suggested that the anion channel has a voltage sensor (effective gating charge 4.3) and a similar collection of local fixed charges on the extra- and intracellular sides as voltage-gated cation channels.
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Blatz AL, Magleby KL (1983) Single voltage-dependent chloride-selective channels of large conductance in cultured rat muscle. Biophys J 43:237–241
Blatz AL, Magleby KL (1985) Single chloride-selective channels active at resting membrane potentials in cultured rat skeletal muscle. Biophys J 47:119–123
Blatz AL, Magleby KL (1986) Quantitative description of three modes of activity of fast chloride channels from rat skeletal muscle. J Physiol (Lond) 378:141–174
Chandler WK, Hodgkin AL, Meves H (1965) The effect of changing the internal solution on sodium inactivation and related phenomena in giant axons. J Physiol (Lond) 180:821–836
Cherksey BD, Zeuthen T (1987) A membrane protein with a K+ and a Cl− channel. Acta Physiol Scand 129:137–138
Coulombe A, Duclohier H, Coraboeuf E, Touzet N (1987) Single chloride-permeable channels of large conductance in cultured cardiac cells of new-born rats. Eur Biophys J 14:155–162
Drouin H, Neumcke B (1974) Specific and unspecific charges at the sodium channels of the nerve membrane. Pflügers Arch 351:207–229
Frankenhaeuser B, Hodgkin AL (1957) The action of calcium on the electrical properties of squid axons. J Physiol (Lond) 137:218–244
Geletyuk VI, Kazachenko VN (1985) Single Cl− channels in molluscan neurones: multiplicity of the conductance states. J Membr Biol 86:9–15
Gray PTA, Bevan S, Ritchie JM (1984) High conductance anion-selective channels in rat cultured Schwann cells. Proc R Soc Lond B 221:395–409
Hanke W, Miller C (1983) Single chloride channels fromTorpedo electroplax. Activation by protons. J Gen Physiol 82:25–45
Hille B (1984) Ionic channels of excitable membranes. Sinauer, Sunderland, MA
Hodgkin AL, Huxley AF (1952) A quantitative description of membrane current and its application to conduction and excitation in nerve. J Physiol (Lond) 117:500–544
Hutter OF, Warner AE (1967) The pH sensitivity of the chloride conductance of frog skeletal muscle. J Physiol (Lond) 189:403–425
Hutter OF, Warner AE (1972) The voltage dependence of the chloride conductance of frog muscle. J Physiol (Lond) 227:275–290
Krouse ME, Schneider GT, Gage PW (1986) A large anion-selective channel has seven conductance levels. Nature 319:58–60
Lux HD, Brown AM (1984) Patch and whole cell calcium currents recorded simultaneously in snail neurons. J Gen Physiol 83:727–750
Schwarze W, Kolb H-A (1984) Voltage-dependent kinetics of an anionic channel of large unit conductance in macrophages and myotube membranes. Pflügers Arch 402:281–291
Shoemaker RL, Frizzell RA, Dwyer TM, Farley JM (1986) Single chloride channel currents from canine tracheal epithelial cells. Biochim Biophys Acta 858:235–242
Woll KH, Neumcke B (1987) Voltage dependence of Cl channels in adult frog skeletal muscle. Pflügers Arch 408 (Suppl 1): R83
Woll KH, Leibowitz MD, Neumcke B, Hille B (1987) A high-conductance anion channel in adult amphibian skeletal muscle. Pflügers Arch 410:632–640
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Woll, K.H., Neumcke, B. Conductance properties and voltage dependence of an anion channel in amphibian skeletal muscle. Pflugers Arch. 410, 641–647 (1987). https://doi.org/10.1007/BF00581325
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DOI: https://doi.org/10.1007/BF00581325