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. 1976 Aug;73(8):2918–2922. doi: 10.1073/pnas.73.8.2918

Presynaptic calcium currents and their relation to synaptic transmission: Voltage clamp study in squid giant synapse and theoretical model for the calcium gate

Rodolfo Llinás 1,2, Izchak Z Steinberg 1,2,*, Kerry Walton 1,2
PMCID: PMC430802  PMID: 183215

Abstract

A voltage clamp study of the presynaptic terminal in squid stellate ganglion has given quantitative results relating inward Ca2+ current to presynaptic membrane potential and postsynaptic response to inward Ca2+ current. The results indicate an S-shaped curve for the relationship between presynaptic potential and Ca2+ current and a linear relationship between Ca2+ current and postsynaptic potential. A similar S-shaped curve was found for the time-dependent properties of the Ca2+ conductance. Based on these results a mathematical model was developed which accounts for the experimental results in this and previously published papers by other authors. The model suggests that five subunits are involved in the Ca2+ gate and that the subunits change noncooperatively from an inactive to an active form upon membrane depolarization.

Keywords: mathematical model, 3-aminopyridine

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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