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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.

  1. Benoit P. R., Mambrini J. Modification of transmitter release by ions which prolong the presynaptic action potential. J Physiol. 1970 Oct;210(3):681–695. doi: 10.1113/jphysiol.1970.sp009235. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Blioch Z. L., Glagoleva I. M., Liberman E. A., Nenashev V. A. A study of the mechanism of quantal transmitter release at a chemical synapse. J Physiol. 1968 Nov;199(1):11–35. doi: 10.1113/jphysiol.1968.sp008637. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Colomo F., Rahamimoff R. Interaction between sodium and calcium ions in the process of transmitter release at the neuromuscular junction. J Physiol. 1968 Sep;198(1):203–218. doi: 10.1113/jphysiol.1968.sp008602. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. DEL CASTILLO J., ENGBAEK L. The nature of the neuromuscular block produced by magnesium. J Physiol. 1954 May 28;124(2):370–384. doi: 10.1113/jphysiol.1954.sp005114. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. DEL CASTILLO J., KATZ B. The effect of magnesium on the activity of motor nerve endings. J Physiol. 1954 Jun 28;124(3):553–559. doi: 10.1113/jphysiol.1954.sp005128. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Dodge F. A., Jr, Rahamimoff R. Co-operative action a calcium ions in transmitter release at the neuromuscular junction. J Physiol. 1967 Nov;193(2):419–432. doi: 10.1113/jphysiol.1967.sp008367. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Gilbert D. L., Ehrenstein G. Effect of divalent cations on potassium conductance of squid axons: determination of surface charge. Biophys J. 1969 Mar;9(3):447–463. doi: 10.1016/S0006-3495(69)86396-4. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Katz B., Miledi R. The release of acetylcholine from nerve endings by graded electric pulses. Proc R Soc Lond B Biol Sci. 1967 Jan 31;167(1006):23–38. doi: 10.1098/rspb.1967.0011. [DOI] [PubMed] [Google Scholar]
  9. Katz B., Miledi R. The timing of calcium action during neuromuscular transmission. J Physiol. 1967 Apr;189(3):535–544. doi: 10.1113/jphysiol.1967.sp008183. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Kelly J. S. The antagonism of Ca2+ by Na+ and other monovalent ions at the frog neuromuscular junction. Q J Exp Physiol Cogn Med Sci. 1968 Jul;53(3):239–249. doi: 10.1113/expphysiol.1968.sp001967. [DOI] [PubMed] [Google Scholar]
  11. Meiri U., Rahamimoff R. Activation of transmitter release by strontium and calcium ions at the neuromuscular junction. J Physiol. 1971 Jul;215(3):709–726. doi: 10.1113/jphysiol.1971.sp009493. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Meiri U., Rahamimoff R. Neuromuscular transmission: inhibition by manganese ions. Science. 1972 Apr 21;176(4032):308–309. doi: 10.1126/science.176.4032.308. [DOI] [PubMed] [Google Scholar]
  13. Mozhayeva G. N., Naumov A. P. Effect of surface charge on the steady-state potassium conductance of nodal membrane. Nature. 1970 Oct 10;228(5267):164–165. doi: 10.1038/228164a0. [DOI] [PubMed] [Google Scholar]
  14. Muller R. U., Finkelstein A. The effect of surface charge on the voltage-dependent conductance induced in thin lipid membranes by monazomycin. J Gen Physiol. 1972 Sep;60(3):285–306. doi: 10.1085/jgp.60.3.285. [DOI] [PMC free article] [PubMed] [Google Scholar]

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