Article date: 1990/3/26
PubMed ID: 1970860
Journal name: Neuroscience letters (ISSN: 0304-3940)
Ibotenate induced a concentration- and largely calcium-dependent release of endogenous glutamate from guinea pig cerebro-cortical synaptosomes. In the absence of Mg2+, the response to ibotenate was enhanced through a mechanism involving N-methyl-D-aspartate (NMDA) receptors; this component was sensitive to the NMDA antagonist 2-amino-7-phosphonoheptanoate (AP7). In the presence of Mg2+, the ibotenate-induced Ca2(+)-dependent release was abolished by L-2-amino-4-phosphonobutyrate (L-AP4). It is suggested that presynaptic 'L-AP4 receptors' exist in guinea pig cerebral cortex, at which ibotenate acts to facilitate glutamate release. L-AP4 may act as an antagonist, or partial agonist of weak intrinsic activity.
Author List: Jones P G, Roberts P J
Publication Types: Journal Article
Substances mentioned in the article: Aminobutyrates; Glutamates; Neurotoxins; Neurotransmitter Agents; Oxazoles; Ibotenic Acid; Glutamic Acid; 2-amino-4-phosphonobutyric acid;
Mesh terms: Aminobutyrates/pharmacology; Animals; Cerebral Cortex/drug effects; Female; Glutamates/metabolism; Glutamic Acid; Guinea Pigs; Ibotenic Acid/pharmacology; In Vitro Techniques; Male; Neurotoxins/pharmacology; Neurotransmitter Agents/metabolism; Oxazoles/pharmacology; Synaptosomes/drug effects;