Biomaterial Database

Tonic GABA-ergic modulation of striatal dopamine release studied by in vivo microdialysis in the freely moving rat. 1995

I Smolders, and N De Klippel, and S Sarre, and G Ebinger, and Y Michotte

Department of Pharmaceutical Chemistry and Drug Analysis, Vrije Universiteit Brussel, Belgium.

GABAA and GABAB receptor agonists and antagonists were administered locally in the striatum of intact and kainic acid lesioned rats. (+/-)-Baclofen, a GABAB receptor agonist, significantly decreased the level of extracellular dopamine in the striatum of intact rats. (+/-)-Phaclofen, a GABAB receptor antagonist, increased the level of extracellular dopamine in the striatum of intact rats and to a lesser extent in the striatum after kainic acid lesion. Pregnanolone (5 beta-pregnan-3 alpha-ol-20-one), a positive allosteric modulator of the GABAA receptor, significantly decreased the level of extracellular dopamine in intact rats. (-)-Bicuculline, a GABAB receptor antagonist, increased the level of extracellular dopamine in the striatum of intact rats, but failed to increase the level of extracellular dopamine after kainic acid lesion. The release of extracellular dopamine, due to infusion of phaclofen or bicuculline, was totally suppressed by tetrodotoxin. These results support a direct influence of GABA on the dopaminergic terminals via presynaptic GABAB receptors, while the effects via the GABAA receptor seem to be postsynaptic and mediated by striatal interneurons or the striatonigral feedback loop.

UI	MeSH Term	Description	Entries
D007395	Interneurons	Most generally any NEURONS which are not motor or sensory. Interneurons may also refer to neurons whose AXONS remain within a particular brain region in contrast to projection neurons, which have axons projecting to other brain regions.	Intercalated Neurons,Intercalated Neuron,Interneuron,Neuron, Intercalated,Neurons, Intercalated
D007608	Kainic Acid	(2S-(2 alpha,3 beta,4 beta))-2-Carboxy-4-(1-methylethenyl)-3-pyrrolidineacetic acid. Ascaricide obtained from the red alga Digenea simplex. It is a potent excitatory amino acid agonist at some types of excitatory amino acid receptors and has been used to discriminate among receptor types. Like many excitatory amino acid agonists it can cause neurotoxicity and has been used experimentally for that purpose.	Digenic Acid,Kainate,Acid, Digenic,Acid, Kainic
D008297	Male		Males
D004298	Dopamine	One of the catecholamine NEUROTRANSMITTERS in the brain. It is derived from TYROSINE and is the precursor to NOREPINEPHRINE and EPINEPHRINE. Dopamine is a major transmitter in the extrapyramidal system of the brain, and important in regulating movement. A family of receptors (RECEPTORS, DOPAMINE) mediate its action.	Hydroxytyramine,3,4-Dihydroxyphenethylamine,4-(2-Aminoethyl)-1,2-benzenediol,Dopamine Hydrochloride,Intropin,3,4 Dihydroxyphenethylamine,Hydrochloride, Dopamine
D005110	Extracellular Space	Interstitial space between cells, occupied by INTERSTITIAL FLUID as well as amorphous and fibrous substances. For organisms with a CELL WALL, the extracellular space includes everything outside of the CELL MEMBRANE including the PERIPLASM and the cell wall.	Intercellular Space,Extracellular Spaces,Intercellular Spaces,Space, Extracellular,Space, Intercellular,Spaces, Extracellular,Spaces, Intercellular
D005246	Feedback	A mechanism of communication within a system in that the input signal generates an output response which returns to influence the continued activity or productivity of that system.	Feedbacks
D005680	gamma-Aminobutyric Acid	The most common inhibitory neurotransmitter in the central nervous system.	4-Aminobutyric Acid,GABA,4-Aminobutanoic Acid,Aminalon,Aminalone,Gammalon,Lithium GABA,gamma-Aminobutyric Acid, Calcium Salt (2:1),gamma-Aminobutyric Acid, Hydrochloride,gamma-Aminobutyric Acid, Monolithium Salt,gamma-Aminobutyric Acid, Monosodium Salt,gamma-Aminobutyric Acid, Zinc Salt (2:1),4 Aminobutanoic Acid,4 Aminobutyric Acid,Acid, Hydrochloride gamma-Aminobutyric,GABA, Lithium,Hydrochloride gamma-Aminobutyric Acid,gamma Aminobutyric Acid,gamma Aminobutyric Acid, Hydrochloride,gamma Aminobutyric Acid, Monolithium Salt,gamma Aminobutyric Acid, Monosodium Salt
D006719	Homovanillic Acid	A 3-O-methyl ETHER of (3,4-dihydroxyphenyl)acetic acid.	3-Methoxy-4-Hydroxyphenylacetic Acid,4-Hydroxy-3-Methoxyphenylacetic Acid,3 Methoxy 4 Hydroxyphenylacetic Acid,4 Hydroxy 3 Methoxyphenylacetic Acid,Acid, 3-Methoxy-4-Hydroxyphenylacetic,Acid, 4-Hydroxy-3-Methoxyphenylacetic,Acid, Homovanillic
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013378	Substantia Nigra	The black substance in the ventral midbrain or the nucleus of cells containing the black substance. These cells produce DOPAMINE, an important neurotransmitter in regulation of the sensorimotor system and mood. The dark colored MELANIN is a by-product of dopamine synthesis.	Nigra, Substantia,Nigras, Substantia,Substantia Nigras