Welcome!
To use the personalized features of this site, please log in or register.
If you have forgotten your username or password, we can help.
My Menu
Saved Items

Roles of IA and morphology in action potential propagation in CA1 pyramidal cell dendrites

Corey D. Acker1, 3 Contact Information and John A. White2, 3

(1)  Department of Neuroscience, University of Connecticut Health Center, 263 Farmington Avenue, Farmington, CT 06030, USA
(2)  Department of Biomedical Engineering, Boston University, 44 Cummington St., Boston, MA 02215, USA
(3)  Department of Biomedical Engineering, Center for BioDynamics, and Center for Memory and Brain, Boston University, Boston, MA, USA

Received: 4 July 2006  Revised: 21 January 2007  Accepted: 8 March 2007  Published online: 20 April 2007

Abstract  Dendrites of CA1 pyramidal cells of the hippocampus, along with those of a wide range of other cell types, support active backpropagation of axonal action potentials. Consistent with previous work, recent experiments demonstrating that properties of synaptic plasticity are different for distal synapses, suggest an important functional role of bAPs, which are known to be prone to failure in distal locations. Using conductance-based models of CA1 pyramidal cells, we show that underlying “traveling wave attractors” control action potential propagation in the apical dendrites. By computing these attractors, we dissect and quantify the effects of IA channels and dendritic morphology on bAP amplitudes. We find that non-uniform activation properties of IA can lead to backpropagation failure similar to that observed experimentally in these cells. Amplitude of forward propagation of dendritic spikes also depends strongly on the activation dynamics of IA. IA channel properties also influence transients at dendritic branch points and whether or not propagation failure results. The branching pattern in the distal apical dendrites, combined with IA channel properties in this region, ensure propagation failure in the apical tuft for a large range of IA conductance densities. At the same time, these same properties ensure failure of forward propagating dendritic spikes initiated in the distal tuft in the absence of some form of cooperativity of synaptic activation.
Electronic supplemary material  The online version of this article (doi:10.1007/s10827-007-0028-8) contains supplementary material, which is available to authorized users.

Keywords  Backpropagation - Propagation failure - Traveling wave attractor - bAP - Dendritic spike

Action Editor: Alain Destexhe

Contact Information Corey D. Acker
Email: acker@uchc.edu
Fulltext Preview (Small, Large)
Image of the first page of the fulltext

References secured to subscribers.

Supplemental Material


Export this article
Export this article as RIS | Text
 
Remote Address: 38.107.191.112 • Server: MPWEB25
HTTP User Agent: CCBot/1.0 (+http://www.commoncrawl.org/bot.html)