Abstract
It is now widely accepted that localized high concentrations of Ca2+ (Ca2+ domains) play a major role in controlling the time course of neurotransmitter release. In the present work we calculate the magnitude and the time course of Ca2+ domains that evolve in the vicinity of a Ca2+ channel and an adjacent release site. In the calculations we consider a accurately dimensioned Ca2+ channel. Moreover, the Ca2+ current is continuously adjusted with regard to the accumulated intracellular Ca2+ and, in addition, endogenous buffers are considered. The calculations, carried out by the software FIDAP, based on finite element method, show that the Ca2+ concentrations achieved near the release sites are significantly lower than claimed by other investigators. Furthermore, we present arguments indicating that the Ca2+ domains, regardless of their magnitude, do not play a role in controlling the time course of release of neurotransmitter.
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Also belongs to the Center for Neural Computation.
Parnas is the Greenfield Professor of Neurobiology.
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Aharon, S., Parnas, H. & Parnas, I. The magnitude and significance of Ca2+ domains for release of neurotransmitter. Bltn Mathcal Biology 56, 1095–1119 (1994). https://doi.org/10.1007/BF02460288
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DOI: https://doi.org/10.1007/BF02460288