Biomaterial Database

Intranigral GR-113808, a selective 5-HT4 receptor antagonist, attenuates morphine-stimulated dopamine release in the rat striatum. 1995

L Pozzi, and L Trabace, and R Invernizzi, and R Samanin

Istituto di Ricerche Farmacologiche, Mario Negri, Milan, Italy.

GR-113808, a potent and selective 5-HT4 receptor antagonist, was infused through a microdialysis probe into the striatum and nucleus accumbens of awake rats, and basal and morphine-stimulated extracellular concentrations of dopamine (DA) were measured in these regions. At 1 and 10 microM GR-113808 did not affect the extracellular concentrations of DA in either region and 100 microM significantly reduced dialysate DA only in the striatum. A subcutaneous dose of 5 mg/kg morphine significantly raised extracellular concentrations of DA in the striatum and nucleus accumbens from 60 to 120 min after injection and the effect was not modified by 10 microM GR-113808 infused through the probe 20 min before and for 60 min after morphine. Bilateral injections of GR-113808 (1, 2.5 and 10 micrograms/0.5 microliter) in the substantia nigra pars compacta did not affect dialysate DA in the striatum, except for a significant increase 120 min after the injection of 10 micrograms but the highest dose of GR-113808 prevented the increase of striatal DA caused by 5 mg/kg morphine s.c. The results suggest that 5-HT4 receptors in the substantia nigra modulate the activity of the dopaminergic nigrostriatal system only when the neurons are activated.

UI	MeSH Term	Description	Entries
D007211	Indoles	Benzopyrroles with the nitrogen at the number one carbon adjacent to the benzyl portion, in contrast to ISOINDOLES which have the nitrogen away from the six-membered ring.
D007267	Injections	Introduction of substances into the body using a needle and syringe.	Injectables,Injectable,Injection
D008297	Male		Males
D009020	Morphine	The principal alkaloid in opium and the prototype opiate analgesic and narcotic. Morphine has widespread effects in the central nervous system and on smooth muscle.	Morphine Sulfate,Duramorph,MS Contin,Morphia,Morphine Chloride,Morphine Sulfate (2:1), Anhydrous,Morphine Sulfate (2:1), Pentahydrate,Oramorph SR,SDZ 202-250,SDZ202-250,Chloride, Morphine,Contin, MS,SDZ 202 250,SDZ 202250,SDZ202 250,SDZ202250,Sulfate, Morphine
D009714	Nucleus Accumbens	Collection of pleomorphic cells in the caudal part of the anterior horn of the LATERAL VENTRICLE, in the region of the OLFACTORY TUBERCLE, lying between the head of the CAUDATE NUCLEUS and the ANTERIOR PERFORATED SUBSTANCE. It is part of the so-called VENTRAL STRIATUM, a composite structure considered part of the BASAL GANGLIA.	Accumbens Nucleus,Nucleus Accumbens Septi,Accumbens Septi, Nucleus,Accumbens Septus, Nucleus,Accumbens, Nucleus,Nucleus Accumbens Septus,Nucleus, Accumbens,Septi, Nucleus Accumbens,Septus, Nucleus Accumbens
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
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
D012702	Serotonin Antagonists	Drugs that bind to but do not activate serotonin receptors, thereby blocking the actions of serotonin or SEROTONIN RECEPTOR AGONISTS.	5-HT Antagonist,5-HT Antagonists,5-Hydroxytryptamine Antagonist,5-Hydroxytryptamine Antagonists,Antiserotonergic Agent,Antiserotonergic Agents,Serotonin Antagonist,Serotonin Blockader,Serotonin Blockaders,Serotonin Receptor Antagonist,Serotonin Receptor Blocker,Antagonists, 5-HT,Antagonists, 5-Hydroxytryptamine,Antagonists, Serotonin,Serotonin Receptor Antagonists,Serotonin Receptor Blockers,5 HT Antagonist,5 HT Antagonists,5 Hydroxytryptamine Antagonist,5 Hydroxytryptamine Antagonists,Agent, Antiserotonergic,Agents, Antiserotonergic,Antagonist, 5-HT,Antagonist, 5-Hydroxytryptamine,Antagonist, Serotonin,Antagonist, Serotonin Receptor,Antagonists, 5 HT,Antagonists, 5 Hydroxytryptamine,Antagonists, Serotonin Receptor,Blockader, Serotonin,Blockaders, Serotonin,Blocker, Serotonin Receptor,Blockers, Serotonin Receptor,Receptor Antagonist, Serotonin,Receptor Antagonists, Serotonin,Receptor Blocker, Serotonin,Receptor Blockers, Serotonin
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