title: [3H]D-aspartic acid release in brain slices of adult and aged Fischer 344 rates.
abstract: Alterations in glutamate content and uptake have been reported to occur in aged animals. The present studies used [3H]D-Aspartic acid [( 3H]-D-ASP) release as a marker for glutamate neurotransmission. Frequency dependent [3H]-D-ASP release was measured in adult (8 month) and aged (28-30 month) Fischer 344 rats. Relatively high stimulation frequencies (greater than 10 Hz) were required to induce [3H]-D-ASP release in both adult and aged F344 rats in temporal cortex and hippocampus. In both brain areas aged animals showed significantly more [3H]-D-ASP release than adult animals. Kainic acid 1 mM failed to induce the release of [3H]-D-ASP in either temporal cortex or hippocampus. Omega conotoxin GVIA (5 x 10(-9) M) a N and L type voltage sensitive calcium channel antagonist failed to inhibit [3H]-D-ASP stimulated release. These results demonstrate an increase in [3H]-D-ASP release in aged compared to adult F344 rats. The data also suggest a novel calcium channel may be involved in [3H]-D-ASP release.
authors.affiliation: Department of Pharmacodynamics, University of Florida, Gainesville 32610.
authors.forename: M J
authors.initials: MJ
authors.lastname: Meldrum
authors.forename: P
authors.initials: P
authors.lastname: Glenton
authors.forename: R
authors.initials: R
authors.lastname: Dawson
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D001224:Aspartic Acid / Q000378:metabolism*; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D015220:Calcium Channels / Q000502:physiology; D004558:Electric Stimulation; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism; D007608:Kainic Acid / Q000494:pharmacology; D008297:Male; D010456:Peptides, Cyclic / Q000494:pharmacology; D051381:Rats; D011916:Rats, Inbred F344; D013702:Temporal Lobe / Q000187:drug effects / Q000378:metabolism; D020866:omega-Conotoxin GVIA
chemical_list: D015220:Calcium Channels; D010456:Peptides, Cyclic; D001224:Aspartic Acid; D020866:omega-Conotoxin GVIA; D007608:Kainic Acid