Linked Life Data

1843751

Source:http://linkedlifedata.com/resource/pubmed/id/1843751

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1993-3-12
pubmed:abstractText
The negative feed-back interaction between horizontal cells (HCs) and cones in the cyprinid fish retina is thought to be mediated by horizontal cell spinules. These are "plastic" structures, largely absent from the dark-adapted retina and formed anew during light adaptation. We have previously shown that horizontal cell feed-back is similarly enhanced by light adaptation. The role of the interplexiform cell transmitter dopamine in both processes has been studied in the roach retina. Application of dopamine to dark-adapted retinae induced spinule formation in a dose-dependent way. The effect of dopamine was mimicked by dibutyryl-cAMP and suppressed selectively by D1 receptor antagonists. The effect of light in inducing spinule formation was lost in retinae depleted of endogenous dopamine. However, application of exogenous dopamine to these retinae triggered normal spinule formation. For all pharmacological treatments used, there was a strong correlation between spinule number and degree of feed-back activity in biphasic horizontal cells. Thus, when the spinule content of the cone pedicles was high, biphasic horizontal cell responses exhibited strong depolarizing components and vice versa. It is concluded that light-evoked formation of spinules in HC dendrites involves the action of dopamine upon D1 receptors. Spinules, in turn, are likely to be presynaptic terminals mediating the dynamic negative feed-back effect of horizontal cells upon cones.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0042-6989
pubmed:author
pubmed:issnType
Print
pubmed:volume
31
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
401-12
pubmed:dateRevised
2009-9-29
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Dopamine and plasticity of horizontal cell function in the teleost retina: regulation of a spectral mechanism through D1-receptors.
pubmed:affiliation
Department of Anatomy and Cell Biology, University of Marburg, F.R.G.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't