Modulation of thalamic neuron excitability by orexins.

Modulation of thalamic neuron excitability by orexins. Research Abstract Details 

Research Abstract Table of Contents

Jump to the:

Modulation of thalamic neuron excitability by orexins. Abstract Text:

G Govindaiah,Charles L Cox,

Orexins (hypocretins) are peptides of hypothalamic origin that play an important role in maintaining wakefulness. Reduced orexin levels have been associated with an increased incidence of narcolepsy. Considering thalamic nuclei are interconnected with virtually all neocortical regions and the thalamus has been found to produce distinct activities related to different levels of arousal, we have examined the actions of orexins on thalamic neurons using an in vitro thalamic slice preparation. The orexins (orexin-A and orexin-B) produced distinct actions within different intralaminar nuclei. Orexin-B strongly depolarized the majority of centrolateral nucleus (CL) neurons (71%), but depolarized a significantly smaller population of parafascicular nuclei (Pf) neurons (10%). In the mediodorsal thalamic nucleus (MD), orexin-B depolarized 21% of the neurons tested. Overall, orexin-B was found to be more potent than Orexin-A. Orexin-A depolarized a significantly smaller population of CL neurons (23%), but had no effect on Pf neurons. In addition, orexin-A produced a small depolarization in 28% of neurons in the thalamic reticular nucleus (TRN). Both orexin-A and orexin-B had no effect on neurons in the lateral posterior (LP), lateralodorsal (LD), posterior thalamic (Po), ventrobasal (VB) nucleus and lateral geniculate nucleus (LGN). The depolarizing actions of orexins were sufficient to alter the firing mode of these neurons from a burst- to tonic-firing mode. The excitatory actions of orexin-B result from a decrease in the apparent leak potassium current (Kleak). The orexin-B mediated excitation was also attenuated by bupivacaine suggesting the involvement of Kleak current. Further, the actions of orexin-B were occluded by the classical neurotransmitter dopamine, indicating the orexins may share similar ionic mechanisms. Thus, the depolarizing actions of orexins may play a key role in altering the firing mode of thalamic neurons associated with different states of consciousness.

Modulation of thalamic neuron excitability by orexins. Publishing Authors By Initials

G Govindaiah,CL Cox,

For similar abstracts research abstracts see: abstracts research

PUBMED ID PMID:

MEDLINE DATE:

Modulation of thalamic neuron excitability by orexins. Journal Published:

PUBLICATION TYPE: Research Support, N.I.H., Extr

Journal: Neuropharmacology

VOLUME: 51

Page Numbers: 414-25

Journal Abbreviation:

ISSN: 0028-3908

DAY: 19

MONTH: 05

YEAR: 2006

Modulation of thalamic neuron excitability by orexins. Information

Number of References:

LANGUAGE: eng

NlmUniqueID: 236217

Modulation of thalamic neuron excitability by orexins. Keywords Mesh Terms:

KEYWORDS:

MESH TERMS:

Chemical & Substance for Abstract: Modulation of thalamic neuron excitability by orexins. Information

Substance Name:

Registry Number:

Grant and Affiliation Information for Modulation of thalamic neuron excitability by orexins.

AFFILIATION: Department of Molecular and Integrative Physiology, University of Illinois, Urbana, IL 61801, USA.

Country: England

AGENCY:

GRANT:

ACRONYM:

MEDLINETA: Neuropharmacology

REFSOURCE:

DATABASENAME:

ACCESSION NUMBER:

Number Hits: 0

Modulation of thalamic neuron excitability by orexins Related Publications

• Absence of metabotropic glutamate receptor-mediated plasticity in the neocortex of fragile X mice.
• Affinity purification of seminalplasmin and characterization of its interaction with calmodulin.
• Australian parasitological research: now and in 2000.
• CD4+ T cell-dependent reduction in hepatitis C virus-specific humoral immune responses after HIV infection.
• Cancer and the threat of death: the cognitive dynamics of death-thought suppression and its impact on behavioral health intentions.
• Chapter 7: Achievements and limitations of cervical cytology screening.
• Costs of alcohol and drug-involved crime.
• Determination of ciglitazone in dog plasma by reversed-phase high-performance liquid chromatography.
• Effects of adult aging and hearing loss on comprehension of rapid speech varying in syntactic complexity.
• European psychiatry: moving towards integration and harmony.
• Experimental apparatus for the study of photoabsorption processes of multiply charged ions by synchrotron radiation.
• Genetic studies of stuttering in a founder population.
• Hypertonic saline reverses stiffness in a Sprague-Dawley rat model of acute intestinal edema, leading to improved intestinal function.
• Immune effector mechanisms in parasitic infections.
• Measurement of intestinal edema using an impedance analyzer circuit.
• Metabotropic glutamate receptors differentially regulate GABAergic inhibition in thalamus.
• Microcalorimetric investigation of the interaction of calmodulin with seminalplasmin and myosin light chain kinase.
• Modulation of thalamic neuron excitability by orexins.
• News from the WPA Secretariat.
• Non-human primate fetal kidney transcriptome analysis indicates mammalian target of rapamycin (mTOR) is a central nutrient-responsive pathway.
• Only time can tell: unethical research and the passage of time.
• Organized unidirectional waves of ATP hydrolysis within a RecA filament.
• Prenatal methyl mercury exposure from fish consumption and child development: a review of evidence and perspectives from the Seychelles Child Development Study.
• Protection against cryptococcosis by using a murine gamma interferon-producing Cryptococcus neoformans strain.
• Role of the vitamin D receptor in hair follicle biology.
• Studies of pituitary-adrenal-testis interaction in sheep. II. The effects of repeated injections of adrenocorticotrophic hormone outside the breeding season.
• The 12th world congress of psychiatry.
• The 13th World Congress of Psychiatry, Cairo 2005: perspectives from the Secretariat.
• Use of retrovirus expression of interfering RNA to determine the contribution of activated k-ras and ras effector expression to human tumor cell growth.
• Using inhibitors of prenylation to block localization and transforming activity.