Document Detail

Synaptic transmission at visualized sympathetic boutons: stochastic interaction between acetylcholine and its receptors.
MedLine Citation:
PMID:  9083664     Owner:  NLM     Status:  MEDLINE    
Excitatory postsynaptic currents (EPSCs) were recorded with loose patch electrodes placed over visualized boutons on the surface of rat pelvic ganglion cells. At 34 degrees C the time to peak of the EPSC was about 0.7 ms, and a single exponential described the declining phase with a time constant of about 4.0 ms; these times were not correlated with changes in the amplitude of the EPSC. The amplitude-frequency histogram of the EPSC at individual boutons was well described by a single Gaussian-distribution that possessed a variance similar to that of the electrical noise. Nonstationary fluctuation analysis of the EPSCs at a bouton indicated that about 120 ACh receptor channels were available beneath boutons for interaction with a quantum of ACh. The characteristics of these EPSCs were compared with the results of Monte Carlo simulations of the quantal release of 9000 acetylcholine (ACh) molecules onto receptor patches of density 1400 microns-2 and 0.41 micron diameter, using a kinetic scheme of interaction between ACh and the receptors similar to that observed at the neuromuscular junction. The simulated EPSC generated in this way had temporal characteristics similar to those of the experimental EPSC when either the diffusion of the ACh is slowed or allowance is made for a finite period of transmitter release from the bouton. The amplitude of the simulated EPSC then exhibited stochastic fluctuations similar to those of the experimental EPSC.
M R Bennett; L Farnell; W G Gibson; N A Lavidis
Related Documents :
23546124 - Chemical detection with hyperspectral lidar using dual frequency combs.
24785964 - Multiple scattering of polarized light: influence of absorption.
24977814 - Absorption-free bragg reflector using zeeman sublevels in atomic vapor.
15524634 - Molecular to fluid dynamics: the consequences of stochastic molecular motion.
22243314 - Confinement and lattice quantum-electrodynamic electric flux tubes simulated with ultra...
15924374 - Advantages of the use of sr-ft-ir microspectroscopy: applications to cultural heritage.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Biophysical journal     Volume:  72     ISSN:  0006-3495     ISO Abbreviation:  Biophys. J.     Publication Date:  1997 Apr 
Date Detail:
Created Date:  1997-09-02     Completed Date:  1997-09-02     Revised Date:  2009-11-18    
Medline Journal Info:
Nlm Unique ID:  0370626     Medline TA:  Biophys J     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  1595-606     Citation Subset:  IM    
Department of Physiology, University of Sydney, New South Wales, Australia.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Acetylcholine / metabolism*
Ganglia, Sympathetic / metabolism*
Monte Carlo Method
Patch-Clamp Techniques
Presynaptic Terminals / metabolism*
Rats, Inbred Strains
Receptors, Cholinergic / metabolism*
Stochastic Processes
Synaptic Transmission*
Reg. No./Substance:
0/Receptors, Cholinergic; 51-84-3/Acetylcholine

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Collective binding properties of receptor arrays.
Next Document:  Depolarization-induced slowing of Ca2+ channel deactivation in squid neurons.