Linked Life Data

8381630

Source:http://linkedlifedata.com/resource/pubmed/id/8381630

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1993-3-9
pubmed:abstractText
We studied the effect of pertussis toxin (PT) and partial muscarinic antagonism using pirenzepine (PIR) on beta-adrenergic relaxation of muscarinic contraction in 188 tracheal smooth muscle (TSM) preparations from 25 dogs in vitro. Strips of TSM were incubated for 4 h at 37 degrees C in Krebs-Henseleit (K-H) perfusate with or without 10 micrograms/ml of PT. In tissues contracted to target tension (TT; 50% of maximal response to 127 mM potassium-substituted K-H [KCl]) with acetylcholine (ACh), pretreatment with PT decreased the concentration of isoproterenol (ISO) causing 30% relaxation from TT (RC30) from 1.3 +/- 0.8 x 10(-7) M (control) to 2.8 +/- 0.7 x 10(-8) M (p = 0.013). Pretreatment with PT also augmented the maximal relaxation elicited by 10(-5) M ISO. In separate studies, strips of TSM were contracted with ACh; pretreatment with 10(-7) M PIR decreased the concentration of ISO causing 50% relaxation (RC50) from 3.4 +/- 0.6 x 10(-7) to 9.6 +/- 1.5 x 10(-8) M (p = 0.042). Pretreatment with PIR did not affect relaxation elicited by ISO for strips contracted equivalently with KCl. In addition, PIR increased both the potency and efficacy of ISO in relaxing muscarinic contraction in sham-incubated strips of TSM but had no effect after incubation with PT. Neither PT nor PIR affected beta-adrenergic relaxation of TSM contracted with KCl. Our data demonstrate that beta-adrenergic receptor relaxation of muscarinic contraction is augmented by (1) incubation with PT and (2) partial blockade of muscarinic receptors.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0003-0805
pubmed:author
pubmed:issnType
Print
pubmed:volume
147
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
327-31
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Pertussis toxin augments beta-adrenergic relaxation of muscarinic contraction in canine trachealis.
pubmed:affiliation
Department of Medicine, University of Chicago, IL 60637.
pubmed:publicationType
Journal Article, Comparative Study, In Vitro, Research Support, U.S. Gov't, P.H.S.