Abstract
The presence of a low threshold calcium current (ICa,LT) besides the classical (high threshold) calcium current (ICa,HT) is investigated using the whole-cell patch-clamp technique (10) on Cs-loaded frog atrial cells at physiological Ca concentrations. ICa,LT, which inactivates within tens of milliseconds, gives rise to a shoulder in the negative part of the peak current-voltage curve. It is completely abolished by 40 μM Ni while ICa,HT is not modified. Cd (30 μM) decreases ICa,LT by about 50% while ICa,HT is completely abolished.
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Bonvallet, R. A low threshold calcium current recorded at physiological Ca concentrations in single frog atrial cells. Pflugers Arch. 408, 540–542 (1987). https://doi.org/10.1007/BF00585084
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DOI: https://doi.org/10.1007/BF00585084