Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2005-1-20
pubmed:abstractText
Intranigral injection of the transient receptor potential vanilloid subtype 1 (TRPV1; also known as VR1) agonist capsaicin (CAP) into the rat brain, or treatment of rat mesencephalic cultures with CAP, resulted in cell death of dopaminergic (DA) neurons, as visualized by immunocytochemistry. This in vivo and in vitro effect was ameliorated by the TRPV1 antagonist capsazepine (CZP) or iodo-resiniferatoxin, suggesting the direct involvement of TRPV1 in neurotoxicity. In cultures, both CAP and anandamide (AEA), an endogenous ligand for both TRPV1 and cannabinoid type 1 (CB1) receptors, induced degeneration of DA neurons, increases in intracellular Ca2+ ([Ca2+]i), and mitochondrial damage, which were inhibited by CZP, the CB1 antagonist N-(piperidin-1-yl)-5-(4-iodophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide (AM251) or the intracellular Ca2+ chelator BAPTA/AM. We also found that CAP or AEA increased mitochondrial cytochrome c release as well as immunoreactivity to cleaved caspase-3 and that the caspase-3 inhibitor z-Asp-Glu-Val-Asp-fmk protected DA neurons from CAP- or AEA-induced neurotoxicity. Additional studies demonstrated that treatment of mesencephalic cultures with CB1 receptor agonist (6aR)-trans 3-(1,1-dimethylheptyl)-6a,7,10,10a-tetrahydro-1-hydroxy-6,6-dimethyl-6H-dibenzo[b,d] pyran-9-methanol (HU210) also produced degeneration of DA neurons and increases in [Ca2+]i, which were inhibited by AM251 and BAPTA/AM. The CAP-, AEA-, or HU210-induced increases in [Ca2+]i were dependent on extracellular Ca2+, with significantly different patterns of Ca2+ influx. Surprisingly, CZP and AM251 reversed HU210- or CAP-induced neurotoxicity by inhibiting Ca2+ influx, respectively, suggesting the existence of functional cross talk between TRPV1 and CB1 receptors. To our knowledge, this study is the first to demonstrate that the activation of TRPV1 and/or CB1 receptors mediates cell death of DA neurons. Our findings suggest that these two types of receptors, TRPV1 and CB1, may contribute to neurodegeneration in response to endogenous ligands such as AEA.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Arachidonic Acids, http://linkedlifedata.com/resource/pubmed/chemical/Calcium, http://linkedlifedata.com/resource/pubmed/chemical/Capsaicin, http://linkedlifedata.com/resource/pubmed/chemical/Casp3 protein, rat, http://linkedlifedata.com/resource/pubmed/chemical/Caspase 3, http://linkedlifedata.com/resource/pubmed/chemical/Caspases, http://linkedlifedata.com/resource/pubmed/chemical/Cytochromes c, http://linkedlifedata.com/resource/pubmed/chemical/Ion Channels, http://linkedlifedata.com/resource/pubmed/chemical/Ligands, http://linkedlifedata.com/resource/pubmed/chemical/Nerve Tissue Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Polyunsaturated Alkamides, http://linkedlifedata.com/resource/pubmed/chemical/Receptor, Cannabinoid, CB1, http://linkedlifedata.com/resource/pubmed/chemical/TRPV Cation Channels, http://linkedlifedata.com/resource/pubmed/chemical/Trpv1 protein, rat, http://linkedlifedata.com/resource/pubmed/chemical/anandamide
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1529-2401
pubmed:author
pubmed:issnType
Electronic
pubmed:day
19
pubmed:volume
25
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
662-71
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:15659603-Animals, pubmed-meshheading:15659603-Arachidonic Acids, pubmed-meshheading:15659603-Calcium, pubmed-meshheading:15659603-Capsaicin, pubmed-meshheading:15659603-Caspase 3, pubmed-meshheading:15659603-Caspases, pubmed-meshheading:15659603-Cell Death, pubmed-meshheading:15659603-Cells, Cultured, pubmed-meshheading:15659603-Cytochromes c, pubmed-meshheading:15659603-Dopamine, pubmed-meshheading:15659603-Immunohistochemistry, pubmed-meshheading:15659603-Ion Channels, pubmed-meshheading:15659603-Ligands, pubmed-meshheading:15659603-Mesencephalon, pubmed-meshheading:15659603-Mitochondria, pubmed-meshheading:15659603-Nerve Tissue Proteins, pubmed-meshheading:15659603-Neurons, pubmed-meshheading:15659603-Polyunsaturated Alkamides, pubmed-meshheading:15659603-Rats, pubmed-meshheading:15659603-Rats, Sprague-Dawley, pubmed-meshheading:15659603-Receptor, Cannabinoid, CB1, pubmed-meshheading:15659603-Substantia Nigra, pubmed-meshheading:15659603-TRPV Cation Channels
pubmed:year
2005
pubmed:articleTitle
Transient receptor potential vanilloid subtype 1 mediates cell death of mesencephalic dopaminergic neurons in vivo and in vitro.
pubmed:affiliation
Brain Disease Research Center, Ajou University School of Medicine, Suwon 442-749, Korea.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't