Biomaterial Database

Intracerebral microdialysis study of glutamate reuptake in awake, behaving rats. 1997

G M Alexander, and J R Grothusen, and S W Gordon, and R J Schwartzman

Department of Neurology, Allegheny University of the Health Sciences, Philadelphia, PA 19102, USA. alexanderg@auhs.edu

The central nervous system has high-affinity uptake systems for the clearance of amino acid transmitters. These systems are found in both neurons and astrocytes. Previous studies have shown that the uptake of amino acid transmitters by astrocytes in culture can be modulated by adrenergic agents. The objectives of this study were to develop a methodology that evaluates the brain's reuptake capacity for glutamate in awake, behaving animals and to determine whether glutamate reuptake is under alpha-adrenergic regulation in the intact central nervous system. Male Sprague-Dawley rats weighing 250-450 g were used in this study. The extraction fraction of L-[3H]glutamate with [14C]mannitol as a reference was measured. The cortical extraction fraction of L-[3H]glutamate corrected for [14C]mannitol (EL-glu) reaches steady state rapidly and is both stable and repeatable. EL-glu is a measure of L-glutamate reuptake and not metabolism. EL-glu is decreased in a dose-dependent manner by the addition of the glutamate reuptake blocker D,L-threo-beta-hydroxyaspartic acid or unlabeled L- glutamate. In addition, EL-glu is increased in a dose-dependent manner by the alpha1-adrenergic agonist phenylephrine, and this increase is blocked by the alpha-adrenergic antagonist phentolamine.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008353	Mannitol	A diuretic and renal diagnostic aid related to sorbitol. It has little significant energy value as it is largely eliminated from the body before any metabolism can take place. It can be used to treat oliguria associated with kidney failure or other manifestations of inadequate renal function and has been used for determination of glomerular filtration rate. Mannitol is also commonly used as a research tool in cell biological studies, usually to control osmolarity.	(L)-Mannitol,Osmitrol,Osmofundin
D009435	Synaptic Transmission	The communication from a NEURON to a target (neuron, muscle, or secretory cell) across a SYNAPSE. In chemical synaptic transmission, the presynaptic neuron releases a NEUROTRANSMITTER that diffuses across the synaptic cleft and binds to specific synaptic receptors, activating them. The activated receptors modulate specific ion channels and/or second-messenger systems in the postsynaptic cell. In electrical synaptic transmission, electrical signals are communicated as an ionic current flow across ELECTRICAL SYNAPSES.	Neural Transmission,Neurotransmission,Transmission, Neural,Transmission, Synaptic
D009638	Norepinephrine	Precursor of epinephrine that is secreted by the ADRENAL MEDULLA and is a widespread central and autonomic neurotransmitter. Norepinephrine is the principal transmitter of most postganglionic sympathetic fibers, and of the diffuse projection system in the brain that arises from the LOCUS CERULEUS. It is also found in plants and is used pharmacologically as a sympathomimetic.	Levarterenol,Levonorepinephrine,Noradrenaline,Arterenol,Levonor,Levophed,Levophed Bitartrate,Noradrenaline Bitartrate,Noradrénaline tartrate renaudin,Norepinephrin d-Tartrate (1:1),Norepinephrine Bitartrate,Norepinephrine Hydrochloride,Norepinephrine Hydrochloride, (+)-Isomer,Norepinephrine Hydrochloride, (+,-)-Isomer,Norepinephrine d-Tartrate (1:1),Norepinephrine l-Tartrate (1:1),Norepinephrine l-Tartrate (1:1), (+,-)-Isomer,Norepinephrine l-Tartrate (1:1), Monohydrate,Norepinephrine l-Tartrate (1:1), Monohydrate, (+)-Isomer,Norepinephrine l-Tartrate (1:2),Norepinephrine l-Tartrate, (+)-Isomer,Norepinephrine, (+)-Isomer,Norepinephrine, (+,-)-Isomer
D010296	Parietal Lobe	Upper central part of the cerebral hemisphere. It is located posterior to central sulcus, anterior to the OCCIPITAL LOBE, and superior to the TEMPORAL LOBES.	Brodmann Area 39,Brodmann Area 40,Brodmann Area 5,Brodmann Area 7,Brodmann's Area 39,Brodmann's Area 40,Brodmann's Area 5,Brodmann's Area 7,Inferior Parietal Cortex,Secondary Sensorimotor Cortex,Superior Parietal Lobule,Angular Gyrus,Gyrus Angularis,Gyrus Supramarginalis,Intraparietal Sulcus,Marginal Sulcus,Parietal Cortex,Parietal Lobule,Parietal Region,Posterior Paracentral Lobule,Posterior Parietal Cortex,Praecuneus,Precuneus,Precuneus Cortex,Prelunate Gyrus,Supramarginal Gyrus,Area 39, Brodmann,Area 39, Brodmann's,Area 40, Brodmann,Area 40, Brodmann's,Area 5, Brodmann,Area 5, Brodmann's,Area 7, Brodmann,Area 7, Brodmann's,Brodmanns Area 39,Brodmanns Area 40,Brodmanns Area 5,Brodmanns Area 7,Cortex, Inferior Parietal,Cortex, Parietal,Cortex, Posterior Parietal,Cortex, Precuneus,Cortex, Secondary Sensorimotor,Cortices, Inferior Parietal,Gyrus, Angular,Gyrus, Prelunate,Gyrus, Supramarginal,Inferior Parietal Cortices,Lobe, Parietal,Lobule, Parietal,Lobule, Posterior Paracentral,Lobule, Superior Parietal,Paracentral Lobule, Posterior,Paracentral Lobules, Posterior,Parietal Cortex, Inferior,Parietal Cortex, Posterior,Parietal Cortices,Parietal Cortices, Inferior,Parietal Cortices, Posterior,Parietal Lobes,Parietal Lobule, Superior,Parietal Lobules,Parietal Lobules, Superior,Parietal Regions,Posterior Paracentral Lobules,Posterior Parietal Cortices,Precuneus Cortices,Region, Parietal,Secondary Sensorimotor Cortices,Sensorimotor Cortex, Secondary,Superior Parietal Lobules
D010646	Phentolamine	A nonselective alpha-adrenergic antagonist. It is used in the treatment of hypertension and hypertensive emergencies, pheochromocytoma, vasospasm of RAYNAUD DISEASE and frostbite, clonidine withdrawal syndrome, impotence, and peripheral vascular disease.	Fentolamin,Phentolamine Mesilate,Phentolamine Mesylate,Phentolamine Methanesulfonate,Phentolamine Mono-hydrochloride,Regitine,Regityn,Rogitine,Z-Max,Mesilate, Phentolamine,Mesylate, Phentolamine,Methanesulfonate, Phentolamine,Mono-hydrochloride, Phentolamine,Phentolamine Mono hydrochloride
D010656	Phenylephrine	An alpha-1 adrenergic agonist used as a mydriatic, nasal decongestant, and cardiotonic agent.	(R)-3-Hydroxy-alpha-((methylamino)methyl)benzenemethanol,Metaoxedrin,Metasympatol,Mezaton,Neo-Synephrine,Neosynephrine,Phenylephrine Hydrochloride,Phenylephrine Tannate,Neo Synephrine,Tannate, Phenylephrine
D002250	Carbon Radioisotopes	Unstable isotopes of carbon that decay or disintegrate emitting radiation. C atoms with atomic weights 10, 11, and 14-16 are radioactive carbon isotopes.	Radioisotopes, Carbon
D003243	Consciousness	Sense of awareness of self and of the environment.	Consciousnesses
D005625	Frontal Lobe	The part of the cerebral hemisphere anterior to the central sulcus, and anterior and superior to the lateral sulcus.	Brodmann Area 8,Brodmann's Area 8,Frontal Cortex,Frontal Eye Fields,Lobus Frontalis,Supplementary Eye Field,Area 8, Brodmann,Area 8, Brodmann's,Brodmanns Area 8,Cortex, Frontal,Eye Field, Frontal,Eye Field, Supplementary,Eye Fields, Frontal,Frontal Cortices,Frontal Eye Field,Frontal Lobes,Lobe, Frontal,Supplementary Eye Fields