| Amino acid levels and gamma-aminobutyric acidA receptors in rat neostriatum, cortex, and thalamus after neonatal 6-hydroxydopamine lesion. | |
| | |
MedLine Citation:
|
PMID: 8382266 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
The amino acid gamma-aminobutyric acid (GABA) is the main inhibitory neurotransmitter in brain, and GABAergic neurons have been proposed to play a major role in basal ganglia physiology. In the neostriatum (caudate putamen), medium-sized aspiny interneurons, as well as neostriatal output neurons that project to several brain regions, use GABA as their neurotransmitter. Dopamine fibers arising from the substantia nigra represent a major input to the neostriatum where, besides their classic neurotransmitter role, they are seemingly involved in the regulation of amino acid neurotransmitter release. To further characterize the nature of some of the amino acid/dopamine interactions, selective dopaminergic deafferentations were produced in neonatal rats (3 days postnatal) by intraventricular administration of the neurotoxin 6-hydroxydopamine (6-OHDA); the noradrenergic neurons were protected by prior administration of desmethylimipramine. After a 3-month survival, levels of catecholamines, indoleamines, and amino acids were determined in cingulate cortex, thalamus, and neostriatum. In addition, GABAA receptors were measured in membrane preparations from these three regions, using the specific agonist [3H]muscimol. In the 6-hydroxydopamine-lesioned rats, levels of dopamine and its metabolites homovanillic acid, 3,4-dihydroxyphenylacetic acid, and 3-methoxytyramine were decreased, as expected, in cortex and neostriatum, but remained unmodified in thalamus. In all three regions, serotonin content was increased; its metabolite, 5-hydroxyindole-3-acetic acid, was also elevated, but only in cortex and neostriatum. The levels of GABA were increased in neostriatum and thalamus, but remained unmodified in cortex. Glycine was increased in all three regions examined. There were also increases of phosphatidylethanolamine and serine in thalamus, and of aspartic acid and alanine in neostriatum. The density of GABAA binding sites was increased in neostriatum, but remained unchanged in cortex and thalamus. The changes in amino acid levels and [3H]muscimol binding sites induced by a neonatal 6-hydroxydopamine treatment differ from those found after similar lesions in adult animals, possibly because of the plastic and synaptic rearrangements that can still occur during early postnatal development. The present results also demonstrate that adaptations occur in response to a dopaminergic deafferentation at an early age and that these exhibit a regional specificity. |
| | |
Authors:
|
E Molina-Holgado; K M Dewar; L Grondin; N M van Gelder; T A Reader |
Related Documents
:
|
8193926 - Morphological and gad immunocytochemical properties of the dorsal lateral geniculate nu... 10803966 - Changes in gamma-aminobutyric acid content during beni-koji making. 2051166 - Extracellular acidic sulfur-containing amino acids and gamma-glutamyl peptides in globa... 12891656 - Vigabatrin and newer interventions in succinic semialdehyde dehydrogenase deficiency. 6526266 - The effect of delta-aminolaevulinic acid on the high affinity uptake of aspartic acid b... 8329446 - Lungfish prolactin exhibits close tetrapod relationships. |
Publication Detail:
|
Type: Journal Article; Research Support, Non-U.S. Gov't |
Journal Detail:
|
Title: Journal of neurochemistry Volume: 60 ISSN: 0022-3042 ISO Abbreviation: J. Neurochem. Publication Date: 1993 Mar |
Date Detail:
|
Created Date: 1993-03-24 Completed Date: 1993-03-24 Revised Date: 2006-11-15 |
Medline Journal Info:
|
Nlm Unique ID: 2985190R Medline TA: J Neurochem Country: UNITED STATES |
Other Details:
|
Languages: eng Pagination: 936-45 Citation Subset: IM |
Affiliation:
|
Département de Physiologie, Faculté de Médecine, Université de Montréal, Québec, Canada. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Amino Acids
/
metabolism* Animals Animals, Newborn Biogenic Monoamines / metabolism Cerebral Cortex / drug effects, metabolism*, pathology Corpus Striatum / drug effects, metabolism*, pathology Female Oxidopamine / pharmacology* Rats Rats, Sprague-Dawley Receptors, GABA-A / metabolism* Thalamus / drug effects, metabolism*, pathology |
| Chemical | |
Reg. No./Substance:
|
0/Amino Acids; 0/Biogenic Monoamines; 0/Receptors, GABA-A; 1199-18-4/Oxidopamine |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: A toxin fraction (FTX) from the funnel-web spider poison inhibits dihydropyridine-insensitive Ca2+ c...
Next Document: Antibodies to the human gamma 2 subunit of the gamma-aminobutyric acidA/benzodiazepine receptor.