Abstract
The fractional contribution of Ca to current flow through neuronal-type nicotinic acetylcholine receptor channels was determined by quantitative fluorescence microfluorimetry using fura-2. The method, which has been applied already to several types of cells and channels is described in detail here. At −70 mV and 2 mM external Ca concentration it was found that Ca contributes 2.5% to the net current. The fractional contribution was found to be voltage dependent, increasing at negative potentials e-fold for a 110 mV potential difference. Total non-specific cation current was found to have a bell-shaped dependence on external Ca concentration peaking at 2 mM.
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Zhou, Z., Neher, E. Calcium permeability of nicotinic acetylcholine receptor channels in bovine adrenal chromaffin cells. Pflugers Arch. 425, 511–517 (1993). https://doi.org/10.1007/BF00374879
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DOI: https://doi.org/10.1007/BF00374879