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. 1974 Mar;71(3):923–926. doi: 10.1073/pnas.71.3.923

The Electrostatic Basis of Mg++ Inhibition of Transmitter Release

Robert U Muller 1,2, Alan Finkelstein 1,2
PMCID: PMC388129  PMID: 4362638

Abstract

The inhibition by Mg++ of stimulus-evoked transmitter release is attributed to a decrease in surface potential, Ψ0, on the outer surface of the presynaptic terminal and hence a lower surface calcium concentration, [Ca++]0. Data on the frog neuromuscular junction are quantitatively fit by assuming that there is a negative charge density, σ, on the outer surface of the presynaptic terminal of 6.5 × 1013 charges per cm2 and that simple diffuse double layer theory is applicable. No specific binding of Mg++ or Ca++ is required. Without any additional assumptions, the inhibitory effect of univalent cations is also quantitatively predicted.

Keywords: neuromuscular junction, quantal content, diffuse double layer, Mg++-Ca++ antagonism, Na+-Ca++ antagonism

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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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