Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2011-6-17
pubmed:abstractText
Catecholaminergic neurons in the locus coeruleus (LC) play a role in the ventilatory response to hypercapnia. Here, we show evidence for the involvement of transient receptor potential (TRP) channels. We found that the input resistance was reduced during an exposure to 8% CO(2) in ~35% LC neurons in mouse brain slices, accompanied by depolarization and higher firing activity. The neuronal responses suggest the opening of Na(+) or nonselective cationic channels instead of the closure of K(+) channels. As a major group of cationic channels, the TRP channels are expressed in the brain, some of which are activated by acidic pH. We therefore screened all representative TRP channels using the quantitative real-time PCR analysis. High levels of mRNA expression of TRPC5, TRPM2, and TRPM7 were found in the LC tissue. Of them, the TRPC5 transcript was the most abundant. The TRPC5 channel was activated by extracellular acidification when expressed in human embryonic kidney (HEK) cells. The TRPC5 currents started to be activated at pH 7.4 with pKa 6.9. The TRPC5 currents were also activated by isohydric hypercapnic and intracellular acidosis in a Ca(2+)-dependent manner. Consistently, the LC neurons were stimulated by both extra- and intracellular acidosis. The stimulatory effect of hypercapnia on LC neurons was eliminated by selective TRPC inhibitor SKF-96365 with and without the blockade of synaptic transmission. Single-cell PCR analysis indicated that TRPC5 mRNAs existed in the LC neurons. Thus these results strongly suggest that the TRP channels are likely to play a role in the CO(2) chemosensitivity of LC neurons, especially TRPC5.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/1-(2-(3-(4-methoxyphenyl)propoxy)-4-..., http://linkedlifedata.com/resource/pubmed/chemical/Calcium Channel Blockers, http://linkedlifedata.com/resource/pubmed/chemical/Carbon Dioxide, http://linkedlifedata.com/resource/pubmed/chemical/Excitatory Amino Acid Antagonists, http://linkedlifedata.com/resource/pubmed/chemical/GABA Antagonists, http://linkedlifedata.com/resource/pubmed/chemical/Imidazoles, http://linkedlifedata.com/resource/pubmed/chemical/Picrotoxin, http://linkedlifedata.com/resource/pubmed/chemical/RNA, Messenger, http://linkedlifedata.com/resource/pubmed/chemical/TRPC Cation Channels, http://linkedlifedata.com/resource/pubmed/chemical/TRPM Cation Channels, http://linkedlifedata.com/resource/pubmed/chemical/TRPM2 protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/Trpc5 protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/Trpm7 protein, mouse
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1522-1598
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
105
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2791-801
pubmed:meshHeading
pubmed-meshheading:21430274-Action Potentials, pubmed-meshheading:21430274-Animals, pubmed-meshheading:21430274-Calcium Channel Blockers, pubmed-meshheading:21430274-Carbon Dioxide, pubmed-meshheading:21430274-Electric Stimulation, pubmed-meshheading:21430274-Excitatory Amino Acid Antagonists, pubmed-meshheading:21430274-GABA Antagonists, pubmed-meshheading:21430274-Gene Expression Regulation, pubmed-meshheading:21430274-HEK293 Cells, pubmed-meshheading:21430274-Humans, pubmed-meshheading:21430274-Hydrogen-Ion Concentration, pubmed-meshheading:21430274-Hypercapnia, pubmed-meshheading:21430274-Imidazoles, pubmed-meshheading:21430274-Locus Coeruleus, pubmed-meshheading:21430274-Mice, pubmed-meshheading:21430274-Mice, Inbred C57BL, pubmed-meshheading:21430274-Neurons, pubmed-meshheading:21430274-Patch-Clamp Techniques, pubmed-meshheading:21430274-Picrotoxin, pubmed-meshheading:21430274-RNA, Messenger, pubmed-meshheading:21430274-TRPC Cation Channels, pubmed-meshheading:21430274-TRPM Cation Channels, pubmed-meshheading:21430274-Transfection
pubmed:year
2011
pubmed:articleTitle
Involvement of TRP channels in the CO? chemosensitivity of locus coeruleus neurons.
pubmed:affiliation
Department of Biology, Georgia State University, Atlanta, GA 30302, USA.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural