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Updated: Jul 23, 2026

Monitoring Changes in the Intracellular Calcium Concentration and Synaptic Efficacy in the Mollusc Aplysia
Published on: July 15, 2012
Gating currents associated with sodium and calcium currents in an Aplysia neuron
Abstract:
In a voltage-clamped aplysia neuron (R15), depolarization beyond -30 millivolts produces an inward sodium current. Depolarization beyond -10 millivolts produces an additional inward calcium current with slower kinetics than the sodium current. When these ionic currents have been suppressed and capacitive currents subtracted out, a small outward displacement current can be seen with depolarizations beyond -30 millivolts. An additional, slower displacement current is seen with depolarizations beyond -10 millivolts. The currents have an exponential decay with an increase in rate per 10 degrees C increase in temperature of about 3 and are thought to be sodium and calcium gating currents.
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