Neuroscience 2003 Abstract
| Presentation Number: | 699.11 |
|---|---|
| Abstract Title: | Modeling thalamic burst responses using the native T-type calcium currents of a non-human primate. |
| Authors: |
Fisher, T. L.*1
; Carden, W. B.1,3
; Salinas, E.1
; Alexander, G. M.1
; Daunais, J. B.2,3
; Friedman, D. P.2,3
; Grant, K. A.2,3
; Godwin, D. W.1,3
1Dept. of NeuroBiol. and Anat., Wake Forest Univ. Hlth. Sci., Winston-Salem, NC 2Dept. Physiology and Pharmacol., Wake Forest Univ. Hlth. Sci., Winston-Salem, NC 3Ctr. for the Neurobehavioral Study of Alcohol, Wake Forest Univ. Hlth. Sci., Winston-Salem, NC |
| Primary Theme and Topics |
Sensory Systems - Vision -- Subcortical visual pathways |
| Session: |
699. Visual Thalamus: Neuronal Properties Poster |
| Presentation Time: | Tuesday, November 11, 2003 3:00 PM-4:00 PM |
| Location: | Morial Convention Center - Hall F-I, Board # F21 |
| Keywords: | Monkey, LGN, Ferret, IFB |
Thalamic bursts depend on the low-threshold calcium current IT. They have previously been modeled using an integrate-and-fire-or-burst (IFB) model with parameters derived from in vitro recordings in cats (Smith et al, J Neurophysol, 83:588, 2000). However, using voltage clamp recordings in the macaque thalamus we have observed steeper activation kinetics and a smaller window current (Carden et al, SFN abstr, 2003) than is found in other species. This is important because of the somewhat controversial role of thalamic bursts — although bursts are typical of spindle wave sleep, they may also appear during waking behavior, and information theoretic analyses indicate that they may transmit sensory information. Here we study the responses of an IFB model that incorporates the key kinetic parameters of native IT of the macaque, and compare this model alongside a similar one with parameters derived from our recordings in ferret under the same conditions. The results show many similarities with previous reports based on cat data, and with our own recordings in rat and ferret. However, burst activity varies across preparations in two key features: in the monkey, both greater hyperpolarization and greater depolarizing pulses are required to elicit a burst, and in general, bursts are observed within a much narrower range of stimulation parameters. This study shows that subtle changes in current kinetics may have important functional consequences, and suggests that IT involvement during primate thalamic activity may be different from that proposed based on recordings from other mammals.
Supported by EY11695, AA013246, NRSA AA014063, NS044894-01, AA11997 and SFN. We thank Amy Nelson and Justin Rawley for technical assistance.
Sample Citation:
[Authors]. [Abstract Title]. Program No. XXX.XX. 2003 Neuroscience Meeting Planner. New Orleans, LA: Society for Neuroscience, 2003. Online.
Copyright © 2003-2026 Society for Neuroscience; all rights reserved. Permission to republish any abstract or part of any abstract in any form must be obtained in writing by SfN office prior to publication.
