Linked Life Data

2377398

Source:http://linkedlifedata.com/resource/pubmed/id/2377398

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1990-9-4
pubmed:abstractText
The innervation in airway tissues from young adult (15-26 wk) and fetal (95/115 d gestation) pigs was compared in isolated tracheal and bronchial preparations subjected to electrical field stimulation. End-organ responsiveness to carbachol, substance P, isoprenaline, and VIP was present by 95 d gestation. Electrical field stimulation (0.5-20 Hz, 70 V, 0.5 ms) resulted in a frequency-dependent contraction that was blocked by atropine (10(-6) M) and TTX (10(-6) M) at both ages. However, there was a 10-fold increase in threshold in the fetal airways because contractions were evoked at frequencies of approximately 5 Hz in the fetus compared with 0.5 Hz in the young adult airways. In the young adult airways, there were atropine-resistant contractions at longer pulse durations (1-5 ms, 20 Hz), but not usually in the fetus. The atropine-resistant contractions were not blocked by TTX. Capsaicin (10(-6) M) produced no contraction in the pig airway. In tissues contracted using the ED50 of carbachol, electrical stimulation (1-20 Hz, 70 V, 1 ms) caused marked relaxation, however, compared with those in the young adult, fetal responses were weak or absent. Propranolol (10(-6) M) partially reduced the relaxation of the young adult bronchus (approximately 25%), but it had little effect on responses in the other young adult and fetal preparations. Therefore, the inhibitory innervation of pig airways was predominantly nonadrenergic and the excitatory component was cholinergic. Neither of these components was fully developed in the fetus close to term.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0031-3998
pubmed:author
pubmed:issnType
Print
pubmed:volume
28
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
69-74
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Inhibitory and excitatory responses to field stimulation in fetal and adult pig airway.
pubmed:affiliation
Department of Physiology, University of Western Australia, Nedlands.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't