Linked Life Data

9144637

Source:http://linkedlifedata.com/resource/pubmed/id/9144637

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1997-8-18
pubmed:abstractText
Light responses of retinal ON bipolar cells are mediated by metabotropic glutamate receptors selectively activated by L-2-amino-4-phosphonobutyric acid (L-AP4). Antagonists to L-AP4 receptors in ON bipolar cells have not previously been identified. This study examines the electrophysiological effects of (S)-2-amino-2-methyl-4-phosphonobutanoic acid (MAP4), (RS)-4-4-chloro-3,5-dihydroxyphenylglycine (CDHPG) and (RS)-3,4,5-trihydroxyphenylglycine (THPG), at L-AP4 receptors in ON bipolar cells of the amphibian retina. Unlike its actions in spinal cord, in retinal ON bipolar cells MAP4 is a weak agonist which exhibits no detectable antagonism to L-AP4. On the other hand, CDHPG exhibits a mixture of agonist and antagonist properties. Addition of Co2+ and oxygenation of CDHPG turns the solution brown and enhances antagonist effects, suggesting that the antagonism reflects actions of a breakdown product of CDHPG. Although THPG did not prove to be this breakdown product, it also has electrophysiological effects consistent with an L-AP4 receptor antagonist. The results suggest that THPG and breakdown products of CDHPG may be antagonists to L-AP4 receptors in retinal ON bipolar cells, although the possibility that these compounds antagonize effects of L-AP4 by acting at some site in the transduction pathway of L-AP4 receptors cannot yet be excluded.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0028-3908
pubmed:author
pubmed:issnType
Print
pubmed:volume
36
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
13-20
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Two phenylglycine derivatives antagonize responses to L-AP4 in ON bipolar cells of the amphibian retina.
pubmed:affiliation
Department of Ophthalmology, University of Nebraska Medical Center, Omaha 68198-5540, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't