Linked Life Data

11370014

Source:http://linkedlifedata.com/resource/pubmed/id/11370014

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2001-5-22
pubmed:abstractText
The autonomic regions of the thoracolumbar spinal cord receive a dense enkephalinergic (ENK) innervation from supraspinal sources, including the rostral ventrolateral medulla (RVLM). In the present study, we sought to determine whether the barosensitive bulbospinal (BSBS) neurons of the RVLM express preproenkephalin (PPE) mRNA. After injection of Fluoro-Gold (FG) into the upper thoracic spinal cord, neurons with PPE mRNA (PPE(+) neurons) were retrogradely labeled throughout the ventrolateral medulla. At the most rostral RVLM level, 29% of bulbospinal PPE+ cells were tyrosine hydroxylase-immunoreactive (TH-ir) and the latter constituted 19.4% of the bulbospinal TH-ir cells. We determined whether the bulbospinal PPE(+) RVLM neurons are barosensitive in two ways. First, we examined Fos production by FG-labeled RVLM neurons after 2 hours of hydralazine-induced hypotension (to 73 +/- 2 mm Hg) in conscious rats. Hydralazine (10 mg/kg i.v.) increased the number of Fos-ir neurons by two- to eightfold at all levels of the ventrolateral medulla examined. In the RVLM, 54% of bulbospinal PPE(+) neurons were Fos-ir, whereas such cells were more rarely found at caudal ventrolateral medullary levels. Second, we recorded individual BSBS RVLM units extracellularly in anesthetized rats and filled them juxtacellularly with biotinamide. Most biotinamide-filled neurons were PPE(+) (10 of 17), and the PPE(+) BSBS cells had a faster axonal conduction velocity than those without PPE mRNA (4.2 vs. 0.67 m/sec). Four of the 10 PPE(+) BSBS RVLM neurons were TH-ir. In summary, PPE mRNA is predominantly expressed by RVLM BSBS neurons with lightly myelinated spinal axons. PPE mRNA is present in most noncatecholaminergic BSBS neurons and also in approximately 20% of the bulbospinal C1 neurons. BSBS RVLM neurons most likely provide a major ENK input to sympathetic preganglionic neurons and PPE mRNA is the first identified positive phenotype of the non-C1 BSBS RVLM neurons.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9967
pubmed:author
pubmed:copyrightInfo
Copyright 2001 Wiley-Liss, Inc.
pubmed:issnType
Print
pubmed:day
18
pubmed:volume
435
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
111-26
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:11370014-Anesthesia, pubmed-meshheading:11370014-Animals, pubmed-meshheading:11370014-Blood Pressure, pubmed-meshheading:11370014-Consciousness, pubmed-meshheading:11370014-Enkephalins, pubmed-meshheading:11370014-Gene Expression, pubmed-meshheading:11370014-Hypotension, pubmed-meshheading:11370014-In Situ Hybridization, pubmed-meshheading:11370014-Male, pubmed-meshheading:11370014-Medulla Oblongata, pubmed-meshheading:11370014-Neural Pathways, pubmed-meshheading:11370014-Neurons, pubmed-meshheading:11370014-Pressoreceptors, pubmed-meshheading:11370014-Protein Precursors, pubmed-meshheading:11370014-Proto-Oncogene Proteins c-fos, pubmed-meshheading:11370014-RNA, Messenger, pubmed-meshheading:11370014-Rats, pubmed-meshheading:11370014-Rats, Sprague-Dawley, pubmed-meshheading:11370014-Spinal Cord, pubmed-meshheading:11370014-Sympathetic Nervous System, pubmed-meshheading:11370014-Tyrosine 3-Monooxygenase
pubmed:year
2001
pubmed:articleTitle
Preproenkephalin mRNA is expressed by C1 and non-C1 barosensitive bulbospinal neurons in the rostral ventrolateral medulla of the rat.
pubmed:affiliation
Department of Pharmacology, University of Virginia Health System, Charlottesville, Virginia 22908-0735, USA. rs3j@virginia.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.