Modeling Starburst cells' GABA(B) receptors and their putative role in motion sensitivity Journal Article


Authors: Grzywacz, Norberto M.; Zucker, Charles L.
Article Title: Modeling Starburst cells' GABA(B) receptors and their putative role in motion sensitivity
Abstract: Neal and Cunningham (Neal, M. J., and J. R. Cunningham. 1995. J. Physiol. (Lond.). 482:363-372) showed that GABA(B) agonists and glycinergic antagonists enhance the light-evoked release of retinal acetylcholine. They proposed that glycinergic cells inhibit the cholinergic Starburst amacrine cells and are in turn inhibited by GABA through GABA(B) receptors. However, as recently shown, glycinergic cells do not appear to have GABA(B) receptors. In contrast, the Starburst amacrine cell has GABA(B) receptors in a subpopulation of its varicosities. We thus propose an alternate model in which GABA(B)-receptor activation reduces the release of ACh from some dendritic compartments onto a glycinergic cell, which then feeds back and inhibits the Starburst cell. In this model, the GABA necessary to make these receptors active comes from the Starburst cell itself, making them autoreceptors. Computer simulations of this model show that it accounts quantitatively for the Neal and Cunningham data. We also argue that GABA(B) receptors could work to increase the sensitivity to motion over other stimuli.
Journal Title: Biophysical journal
Volume: 91
Issue: 2
ISSN: 0006-3495
Publisher: Biophysical Society  
Date Published: 2006
Start Page: 473
End Page: 486
Language: eng
DOI/URL:
Notes: undefined; J2: Biophys J