Linked Life Data

16192383

Source:http://linkedlifedata.com/resource/pubmed/id/16192383

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
39
pubmed:dateCreated
2005-9-29
pubmed:abstractText
Camphor is a naturally occurring compound that is used as a major active ingredient of balms and liniments supplied as topical analgesics. Despite its long history of common medical use, the underlying molecular mechanism of camphor action is not understood. Capsaicin and menthol, two other topically applied agents widely used for similar purposes, are known to excite and desensitize sensory nerves by acting on two members of transient receptor potential (TRP) channel superfamily: heat-sensitive TRP vanilloid subtype 1 (TRPV1) and cold-sensitive TRP channel M8, respectively. Camphor has recently been shown to activate TRPV3, and here we show that camphor also activates heterologously expressed TRPV1, requiring higher concentrations than capsaicin. Activation was enhanced by phospholipase C-coupled receptor stimulation mimicking inflamed conditions. Similar camphor-activated TRPV1-like currents were observed in isolated rat DRG neurons and were strongly potentiated after activation of protein kinase C with phorbol-12-myristate-13-acetate. Camphor activation of rat TRPV1 was mediated by distinct channel regions from capsaicin, as indicated by camphor activation in the presence of the competitive inhibitor capsazepine and in a capsaicin-insensitive point mutant. Camphor did not activate the capsaicin-insensitive chicken TRPV1. TRPV1 desensitization is believed to contribute to the analgesic actions of capsaicin. We found that, although camphor activates TRPV1 less effectively, camphor application desensitized TRPV1 more rapidly and completely than capsaicin. Conversely, TRPV3 current sensitized after repeated camphor applications, which is inconsistent with the analgesic role of camphor. We also found that camphor inhibited several other related TRP channels, including ankyrin-repeat TRP 1 (TRPA1). The camphor-induced desensitization of TRPV1 and block of TRPA1 may underlie the analgesic effects of camphor.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1529-2401
pubmed:author
pubmed:issnType
Electronic
pubmed:day
28
pubmed:volume
25
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
8924-37
pubmed:dateRevised
2011-7-11
pubmed:meshHeading
pubmed-meshheading:16192383-Animals, pubmed-meshheading:16192383-Ankyrins, pubmed-meshheading:16192383-Calcium Channels, pubmed-meshheading:16192383-Camphor, pubmed-meshheading:16192383-Capsaicin, pubmed-meshheading:16192383-Cell Line, pubmed-meshheading:16192383-Drug Synergism, pubmed-meshheading:16192383-Electric Conductivity, pubmed-meshheading:16192383-Electrophysiology, pubmed-meshheading:16192383-Ganglia, Spinal, pubmed-meshheading:16192383-Hot Temperature, pubmed-meshheading:16192383-Humans, pubmed-meshheading:16192383-Ion Channels, pubmed-meshheading:16192383-Neurons, pubmed-meshheading:16192383-Rats, pubmed-meshheading:16192383-Rats, Sprague-Dawley, pubmed-meshheading:16192383-TRPV Cation Channels, pubmed-meshheading:16192383-Tachyphylaxis, pubmed-meshheading:16192383-Tetradecanoylphorbol Acetate
pubmed:year
2005
pubmed:articleTitle
Camphor activates and strongly desensitizes the transient receptor potential vanilloid subtype 1 channel in a vanilloid-independent mechanism.
pubmed:affiliation
Howard Hughes Medical Institute, Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural