Linked Life Data

15157705

Source:http://linkedlifedata.com/resource/pubmed/id/15157705

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2004-5-25
pubmed:abstractText
In the peripheral nervous system, N-methyl-D-aspartate receptors (NMDAR) expressed on the central and peripheral terminals of primary afferent neurons are involved in nociception. We used single cell imaging of intracellular calcium concentration ([Ca2+]i) and patch clamp techniques to characterize the functional properties of NMDARs on adult rat dorsal root ganglia (DRG) neurons in primary culture and selectively on those innervating the distal colon. In Mg2+-free extracellular solution, rapid perfusion of DRG neurons with 250 microM NMDA and 10 microM glycine caused a significant increase in [Ca2+]i, and elicited inward currents in whole cell patch clamp recordings when the holding potential was -60 mV. Both effects were reversibly inhibited by 200 microM ketamine in a use-dependent manner. The EC50 values for NMDA and glycine were 64 and 1.9 microM with Hill slope coefficients of 1.4 and 1.3, respectively. At negative potentials, extracellular Mg2+ blocked currents in a concentration- and voltage-dependent manner. The IC50 for Mg2+ at a holding potential of -100 mV was 2.0 microM. The NMDAR subtype-selective antagonist, ifenprodil, inhibited 94% of the NMDA and glycine-induced current with an IC50 of 2.6 microM. There was no evidence of multiple binding sites for ifenprodil. There was no significant difference in the NMDAR current density on DRG neurons that had innervated the colon, nor was there a difference in the EC50 for ifenprodil. These results demonstrate that functional NMDARs expressed by DRG neurons innervating both somatic and visceral tissues of adult rats are composed predominantly of NR2B subunits.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0304-3959
pubmed:author
pubmed:issnType
Print
pubmed:volume
109
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
443-52
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:15157705-Animals, pubmed-meshheading:15157705-Calcium, pubmed-meshheading:15157705-Calcium Signaling, pubmed-meshheading:15157705-Cells, Cultured, pubmed-meshheading:15157705-Colon, pubmed-meshheading:15157705-Dose-Response Relationship, Drug, pubmed-meshheading:15157705-Excitatory Amino Acid Antagonists, pubmed-meshheading:15157705-Ganglia, Spinal, pubmed-meshheading:15157705-Glycine, pubmed-meshheading:15157705-Magnesium, pubmed-meshheading:15157705-Membrane Potentials, pubmed-meshheading:15157705-N-Methylaspartate, pubmed-meshheading:15157705-Neurons, Afferent, pubmed-meshheading:15157705-Nociceptors, pubmed-meshheading:15157705-Pain, pubmed-meshheading:15157705-Patch-Clamp Techniques, pubmed-meshheading:15157705-Rats, pubmed-meshheading:15157705-Rats, Sprague-Dawley, pubmed-meshheading:15157705-Receptors, N-Methyl-D-Aspartate, pubmed-meshheading:15157705-Visceral Afferents
pubmed:year
2004
pubmed:articleTitle
Electrophysiological characterization of N-methyl-D-aspartate receptors in rat dorsal root ganglia neurons.
pubmed:affiliation
Division of Digestive Diseases, Department of Medicine, Center for Neurovisceral Sciences (CNS) and Women's Health, University of California, Warren Hall, Room 14-103, 900 Veterans Avenue, Los Angeles, CA 90095, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.