Linked Life Data

18590803

Source:http://linkedlifedata.com/resource/pubmed/id/18590803

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2008-8-20
pubmed:abstractText
The present study used an in vitro brainstem preparation from pre-metamorphic tadpoles and adult bullfrogs (Lithobates catesbeiana) to understand the neural mechanisms associated with central O(2) chemosensitivity and its maturation. In this species, brainstem hypoxia increases fictive lung ventilation in tadpoles but decreases in adults. Previous studies have shown that alpha(1)-adrenoceptor inactivation prevents these responses, suggesting that noradrenergic neurons are involved. We first tested the hypothesis that the pons (which includes noradrenergic neurons from the locus coeruleus; LC) plays a role in the lung burst frequency response to central hypoxia by comparing the effects of brainstem transection at the LC level between pre-metamorphic tadpoles and adults. Data show that brainstem transection prevents the lung burst frequency response in both stage groups. During development, the progressive decrease in the Na(+)/K(+)/Cl(-) co-transporter NKCC1 contributes to the maturation of neural networks. Because NKCC1 becomes activated during hypoxia, we then tested the hypothesis that NKCC1 contributes to maturation of the central O(2) chemoreflex. Double labeling experiments showed that the proportion of tyrosine hydroxylase positive neurons expressing NKCC1 in the LC decreases during development. Inactivation of NKCC1 with bumetanide bath application reversed the lung burst response to hypoxia in tadpoles. Bumetanide inhibited the response in adults. These data indicate that a structure within the pons (potentially the LC) is necessary to the central hypoxic chemoreflex and demonstrate that NKCC1 plays a role in central O(2) chemosensitivity and its maturation in this species.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0306-4522
pubmed:author
pubmed:issnType
Print
pubmed:day
26
pubmed:volume
155
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
983-96
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Role of pontine neurons in central O(2) chemoreflex during development in bullfrogs (Lithobates catesbeiana).
pubmed:affiliation
Department of Pediatrics, Université Laval, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec City, QC, Canada.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't