| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Biophys J, November 1999, p. 2418-2429, Vol. 77, No. 5
Abt. Membranbiophysik, Max-Planck-Institut für biophysikalische Chemie, Am Fassberg 11, D-37077 Göttingen, Germany
We explore the properties of models of synaptic vesicle
dynamics, in which synaptic depression is attributed to depletion of a
pool of release-ready vesicles. Two alternative formulations of the
model allow for either recruitment of vesicles from an unlimited
reserve pool (vesicle state model) or for recovery of a fixed number of
release sites to a release-ready state (release-site model). It is
assumed that, following transmitter release, the recovery of the
release-ready pool of vesicles is regulated by the intracellular free
Ca++ concentration, [Ca++]i.
Considering the kinetics of [Ca++]i after
single presynaptic action potentials, we show that pool recovery can be
described by two distinct kinetic components. With such a model,
complex kinetic and steady-state properties of synaptic depression as
found in several types of synapses can be accurately described.
However, the specific assumption that enhanced recovery is proportional
to [Ca++]i, as measured with Ca++
indicator dyes, is not confirmed by experiments at the calyx of Held,
in which [Ca++]i-homeostasis was altered by
adding low concentrations of the exogenous Ca++ buffer,
fura-2, to the presynaptic terminal. We conclude that synaptic
depression at the calyx of Held is governed by localized, near membrane
[Ca++]i signals not visible to the indicator
dye, or else by an altogether different mechanism. We demonstrate that,
in models in which a Ca++-dependent process is linearly
related to [Ca++]i, the addition of buffers
has only transient but not steady-state consequences.
Biophys J, November 1999, p. 2418-2429, Vol. 77, No. 5
© 1999 by the Biophysical Society 0006-3495/99/11/2418/12 $2.00
This article has been cited by other articles:
 |
|
 |
|
  M. H. Hennig, M. Postlethwaite, I. D. Forsythe, and B. P. Graham Interactions between multiple sources of short-term plasticity during evoked and spontaneous activity at the rat calyx of Held J. Physiol., July 1, 2008; 586(13): 3129 - 3146. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Yang and M. A. Xu-Friedman Relative Roles of Different Mechanisms of Depression at the Mouse Endbulb of Held J Neurophysiol, May 1, 2008; 99(5): 2510 - 2521. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 N. Hosoi, T. Sakaba, and E. Neher Quantitative Analysis of Calcium-Dependent Vesicle Recruitment and Its Functional Role at the Calyx of Held Synapse J. Neurosci., December 26, 2007; 27(52): 14286 - 14298. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. Neher Short-Term Plasticity Turns Plastic. Focus on "Synaptic Transmission at the Calyx of Held Under In Vivo-Like Activity Levels" J Neurophysiol, August 1, 2007; 98(2): 577 - 578. [Full Text] [PDF]
|
|
|
|
|
|
K. M. MacLeod, T. K. Horiuchi, and C. E. Carr A Role for Short-Term Synaptic Facilitation and Depression in the Processing of Intensity Information in the Auditory Brain Stem J Neurophysiol, April 1, 2007; 97(4): 2863 - 2874. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Kushmerick, R. Renden, and H. von Gersdorff Physiological Temperatures Reduce the Rate of Vesicle Pool Depletion and Short-Term Depression via an Acceleration of Vesicle Recruitment J. Neurosci., February 1, 2006; 26(5): 1366 - 1377. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Korogod, X. Lou, and R. Schneggenburger Presynaptic Ca2+ Requirements and Developmental Regulation of Posttetanic Potentiation at the Calyx of Held J. Neurosci., May 25, 2005; 25(21): 5127 - 5137. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. Fuhrmann, A. Cowan, I. Segev, M. Tsodyks, and C. Stricker Multiple mechanisms govern the dynamics of depression at neocortical synapses of young rats J. Physiol., June 1, 2004; 557(2): 415 - 438. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Trommershauser, R. Schneggenburger, A. Zippelius, and E. Neher Heterogeneous Presynaptic Release Probabilities: Functional Relevance for Short-Term Plasticity Biophys. J., March 1, 2003; 84(3): 1563 - 1579. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Li and R. E. Burke Developmental Changes in Short-Term Synaptic Depression in the Neonatal Mouse Spinal Cord J Neurophysiol, December 1, 2002; 88(6): 3218 - 3231. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Luthi, G. Di Paolo, O. Cremona, L. Daniell, P. De Camilli, and D. A. McCormick Synaptojanin 1 Contributes to Maintaining the Stability of GABAergic Transmission in Primary Cultures of Cortical Neurons J. Neurosci., December 1, 2001; 21(23): 9101 - 9111. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Brenowitz and L. O. Trussell Maturation of Synaptic Transmission at End-Bulb Synapses of the Cochlear Nucleus J. Neurosci., December 1, 2001; 21(23): 9487 - 9498. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. C. Meyer, E. Neher, and R. Schneggenburger Estimation of Quantal Size and Number of Functional Active Zones at the Calyx of Held Synapse by Nonstationary EPSC Variance Analysis J. Neurosci., October 15, 2001; 21(20): 7889 - 7900. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Li and R. E. Burke Short-Term Synaptic Depression in the Neonatal Mouse Spinal Cord: Effects of Calcium and Temperature J Neurophysiol, May 1, 2001; 85(5): 2047 - 2062. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Brenowitz and L. O. Trussell Minimizing Synaptic Depression by Control of Release Probability J. Neurosci., March 15, 2001; 21(6): 1857 - 1867. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Sakaba and E. Neher Quantitative Relationship between Transmitter Release and Calcium Current at the Calyx of Held Synapse J. Neurosci., January 15, 2001; 21(2): 462 - 476. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. Dinkelacker, T. Voets, E. Neher, and T. Moser The Readily Releasable Pool of Vesicles in Chromaffin Cells Is Replenished in a Temperature-Dependent Manner and Transiently Overfills at 37{degrees}C J. Neurosci., November 15, 2000; 20(22): 8377 - 8383. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
U. Kraushaar and P. Jonas Efficacy and Stability of Quantal GABA Release at a Hippocampal Interneuron-Principal Neuron Synapse J. Neurosci., August 1, 2000; 20(15): 5594 - 5607. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
