Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2004-2-19
pubmed:abstractText
Inhibition of primary afferent neurons contributes to the antihyperalgesic effects of opioid and CB1 receptor agonists. Two bioassays were used to compare the effects of the CB1 receptor agonist CP 55,940 and morphine on dissociated adult rat DRG neurons. Both agonists inhibited the increase in free intracellular Ca2+ concentration evoked by depolarization; however, effects of CP 55,940 occurred primarily in large neurons (cell area, >800 microm2), whereas morphine inhibited the response in smaller neurons. Cotreatment with selective blockers of L-, N-, and P/Q-type voltage-dependent Ca2+ channels indicated that CB1 receptors on DRG neurons couple solely with N-type channels but opioid receptors couple with multiple subtypes. Experiments with selective agonists and antagonists of opioid receptors indicated that mu and delta, but not kappa, receptors contributed to the inhibitory effect of morphine on voltage-dependent Ca2+ influx. Because Ca2+ channels underlie release of transmitters from neurons, the effects of opioid agonists and CP 55,940 on depolarization-evoked release of calcitonin gene-related peptide (CGRP) were compared. Morphine inhibited release through delta receptors but CP 55,940 had no effect. Colocalization of CGRP with delta-opioid but not mu-opioid or CB1 receptor immunoreactivity in superficial laminae of the dorsal horn of the spinal cord was consistent with the data for agonist inhibition of peptide release. Therefore, CB1 and opioid agonists couple with different voltage-dependent Ca2+ channels in different populations of DRG neurons. Furthermore, differences occur in the distribution of receptors between the cell body and terminals of DRG neurons. The complementary action of CB1 and opioid receptor agonists on populations of DRG neurons provides a rationale for their combined use in modulation of somatosensory input to the spinal cord.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/3-(2-hydroxy-4-(1,1-dimethylheptyl)p..., http://linkedlifedata.com/resource/pubmed/chemical/Calcitonin Gene-Related Peptide, http://linkedlifedata.com/resource/pubmed/chemical/Calcium, http://linkedlifedata.com/resource/pubmed/chemical/Calcium Channel Blockers, http://linkedlifedata.com/resource/pubmed/chemical/Calcium Channels, http://linkedlifedata.com/resource/pubmed/chemical/Cyclohexanols, http://linkedlifedata.com/resource/pubmed/chemical/Morphine, http://linkedlifedata.com/resource/pubmed/chemical/Narcotic Antagonists, http://linkedlifedata.com/resource/pubmed/chemical/Narcotics, http://linkedlifedata.com/resource/pubmed/chemical/Pertussis Toxin, http://linkedlifedata.com/resource/pubmed/chemical/Potassium, http://linkedlifedata.com/resource/pubmed/chemical/Receptor, Cannabinoid, CB1, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Opioid
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1529-2401
pubmed:author
pubmed:issnType
Electronic
pubmed:day
18
pubmed:volume
24
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1744-53
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:14973253-Animals, pubmed-meshheading:14973253-Biological Assay, pubmed-meshheading:14973253-Calcitonin Gene-Related Peptide, pubmed-meshheading:14973253-Calcium, pubmed-meshheading:14973253-Calcium Channel Blockers, pubmed-meshheading:14973253-Calcium Channels, pubmed-meshheading:14973253-Cells, Cultured, pubmed-meshheading:14973253-Cyclohexanols, pubmed-meshheading:14973253-Ganglia, Spinal, pubmed-meshheading:14973253-Male, pubmed-meshheading:14973253-Morphine, pubmed-meshheading:14973253-Narcotic Antagonists, pubmed-meshheading:14973253-Narcotics, pubmed-meshheading:14973253-Neurons, pubmed-meshheading:14973253-Pertussis Toxin, pubmed-meshheading:14973253-Potassium, pubmed-meshheading:14973253-Rats, pubmed-meshheading:14973253-Rats, Sprague-Dawley, pubmed-meshheading:14973253-Receptor, Cannabinoid, CB1, pubmed-meshheading:14973253-Receptors, Opioid, pubmed-meshheading:14973253-Spinal Cord
pubmed:year
2004
pubmed:articleTitle
Differential effects of CB1 and opioid agonists on two populations of adult rat dorsal root ganglion neurons.
pubmed:affiliation
Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S.