Linked Life Data

9547245

Source:http://linkedlifedata.com/resource/pubmed/id/9547245

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
1998-5-5
pubmed:abstractText
Perception of hue is opponent, involving the antagonistic comparison of signals from different cone types. For blue versus yellow opponency, the antagonism is first evident at a ganglion cell with firing that increases to stimulation of short wavelength-sensitive (S) cones and decreases to stimulation of middle wavelength-sensitive (M) and long wavelength-sensitive (L) cones. This ganglion cell, termed blue-yellow (B-Y), has a distinctive morphology with dendrites in both ON and OFF strata of the inner plexiform layer (Dacey and Lee, 1994). Here we report the synaptic circuitry of the cell and its spatial density. Reconstructing neurons in macaque fovea from electron micrographs of serial sections, we identified six ganglion cells that branch in both strata and have similar circuitry. In the ON stratum each cell collects approximately 33 synapses from bipolar cells traced back exclusively to invaginating contacts from S cones, and in the OFF stratum each cell collects approximately 14 synapses from bipolar cells (types DB2 and DB3) traced to basal synapses from approximately 20 M and L cones. This circuitry predicts that spatially coincident blue-yellow opponency arises at the level of the cone output via expression of different glutamate receptors. S cone stimuli suppress glutamate release onto metabotropic receptors of the S cone bipolar cell dendrite, thereby opening cation channels, whereas M and L cone stimuli suppress glutamate release onto ionotropic glutamate receptors of DB2 and DB3 cell dendrites, thereby closing cation channels. Although the B-Y cell is relatively rare (3% of foveal ganglion cells), its spatial density equals that of the S cone; thus it could support psychophysical discrimination of a blue-yellow grating down to the spatial cutoff of the S cone mosaic.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0270-6474
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
18
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3373-85
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Microcircuitry and mosaic of a blue-yellow ganglion cell in the primate retina.
pubmed:affiliation
The Zanvyl Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, Maryland 21218-2685, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.