Calcium-permeable channels in HeLa cells.
نویسندگان
چکیده
Calcium-permeable channels with a slope conductance of 9 pS were revealed in excised inside-out patches of cultured HeLa cells. Over a potential range from -80 to -10 mV, unitary inward currents were recorded with 110 Ca2+ in the pipette in artificial "intracellular" solutions containing impermeant anions. Channel activity was not considerably affected by varying free calcium concentration between 0.01 and 10 mumol/l in cytosol-like solution. In experiments with low spontaneous activity of calcium-permeable channels in the inside-out patch, it could be increased by the application of 5-10 mumol/l inositol-trisphosphate to the inner membrane surface.
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عنوان ژورنال:
- General physiology and biophysics
دوره 12 1 شماره
صفحات -
تاریخ انتشار 1993