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PubMed · 7225510

Presynaptic calcium currents in squid giant synapse.

R Llinás·I Z Steinberg·K Walton
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Abstract

A voltage clamp study has been performed in the presynaptic terminal of the squid stellate ganglion. After blockage of the voltage-dependent sodium and potassium conductances, an inward calcium current is demonstrated. Given a step-depolarization pulse, this voltage- and time-dependent conductance has an S-shaped onset. At the "break" of the voltage step, a rapid tail current is observed. From these results a kinetic model is generated which accounts for the experimental results and predicts for the time course and amplitude a possible calcium entry during presynaptic action potentials.

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Action PotentialsAnimalsCalciumDecapodiformesElectric ConductivityElectric StimulationGangliaKineticsMathematicsMembrane PotentialsSynapsesJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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BibTeXRIS

R Llinás, I Z Steinberg, K Walton. 1981. Presynaptic calcium currents in squid giant synapse.. https://doi.org/10.1016/s0006-3495(81)84898-9

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