Calcium-permeable channels in HeLa cells.
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.
Negulyaev YuA
Institute of Cytology, Russian Academy of Sciences, St. Petersburg.
Savokhina
G A
GA
Vedernikova
E A
EA
D015220:Calcium Channels / Q000187:drug effects / Q000378:metabolism*; D002463:Cell Membrane Permeability; D004553:Electric Conductivity; D006367:HeLa Cells; D006801:Humans; D015544:Inositol 1,4,5-Trisphosphate / Q000494:pharmacology; D007700:Kinetics; D008564:Membrane Potentials
D015220:Calcium Channels; D015544:Inositol 1,4,5-Trisphosphate