Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2006-9-13
pubmed:abstractText
The rat retrotrapezoid nucleus (RTN) contains candidate central chemoreceptors that have extensive dendrites within the marginal layer (ML). This study describes the axonal projections of RTN neurons and their probable synaptic inputs. The ML showed a dense plexus of nerve terminals immunoreactive (ir) for markers of glutamatergic (vesicular glutamate transporters VGLUT1-3), gamma-aminobutyric acid (GABA)-ergic, adrenergic, serotonergic, cholinergic, and peptidergic transmission. The density of VGLUT3-ir terminals tracked the location of RTN chemoreceptors. The efferent and afferent projections of RTN were studied by placing small iontophoretic injections of anterograde (biotinylated dextran amine; BDA) and retrograde (cholera toxin B) tracers where RTN chemoreceptors have been previously recorded. BDA did not label the nearby C1 cells. BDA-ir varicosities were found in the solitary tract nucleus (NTS), all ventral respiratory column (VRC) subdivisions, A5 noradrenergic area, parabrachial complex, and spinal cord. In each target region, a large percentage of the BDA-ir varicosities was VGLUT2-ir (41-83%). Putative afferent input to RTN originated from spinal cord, caudal NTS, area postrema, VRC, dorsolateral pons, raphe nuclei, lateral hypothalamus, central amygdala, and insular cortex. The results suggest that 1) whether or not the ML is specialized for CO(2) sensing, its complex neuropil likely regulates the activity of RTN chemosensitive neurons; 2) the catecholaminergic, cholinergic, and serotonergic innervation of RTN represents a possible substrate for the known state-dependent control of RTN chemoreceptors; 3) VGLUT3-ir terminals are a probable marker of RTN; and 4) the chemosensitive neurons of RTN may provide a chemical drive to multiple respiratory outflows, insofar as RTN innervates the entire VRC.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0021-9967
pubmed:author
pubmed:copyrightInfo
(c) 2006 Wiley-Liss, Inc.
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
499
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
64-89
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Afferent and efferent connections of the rat retrotrapezoid nucleus.
pubmed:affiliation
Department of Pharmacology, University of Virginia, Charlottesville, Virginia 22908, USA. dr5e@virginia.edu
pubmed:publicationType
Journal Article, Comparative Study, Research Support, N.I.H., Extramural