Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1999-9-8
pubmed:abstractText
We determined the dose-response curves to inhaled methacholine (MCh) in 16 asthmatic and 8 healthy subjects with prohibition of deep inhalations (DIs) and with 5 DIs taken after each MCh dose. Flow was measured on partial expiratory flow-volume curves at an absolute lung volume (plethysmographically determined) equal to 25% of control forced vital capacity (FVC). Airway inflammation was assessed in asthmatic subjects by analysis of induced sputum. Even when DIs were prohibited, the dose of MCh causing a 50% decrease in forced partial flow at 25% of control FVC (PD(50)MCh) was lower in asthmatic than in healthy subjects (P < 0.0001). In healthy but not in asthmatic subjects, repeated DIs significantly decreased the maximum response to MCh [from 90 +/- 4 to 62 +/- 8 (SD) % of control, P < 0.001], increased PD(50)MCh (P < 0.005), without affecting the dose causing 50% of maximal response. In asthmatic subjects, neither PD(50)MCh when DIs were prohibited nor changes in PD(50)MCh induced by DIs were significantly correlated with inflammatory cell numbers or percentages in sputum. We conclude that 1) even when DIs are prohibited, the responsiveness to MCh is greater in asthmatic than in healthy subjects; 2) repeated DIs reduce airway responsiveness in healthy but not in asthmatic subjects; and 3) neither airway hyperresponsiveness nor the inability of DIs to relax constricted airways in asthmatic subjects is related to the presence of inflammatory cells in the airways.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
8750-7587
pubmed:author
pubmed:issnType
Print
pubmed:volume
87
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
567-73
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:10444614-Administration, Inhalation, pubmed-meshheading:10444614-Adolescent, pubmed-meshheading:10444614-Adult, pubmed-meshheading:10444614-Airway Resistance, pubmed-meshheading:10444614-Asthma, pubmed-meshheading:10444614-Bronchoconstrictor Agents, pubmed-meshheading:10444614-Cell Count, pubmed-meshheading:10444614-Dose-Response Relationship, Drug, pubmed-meshheading:10444614-Eosinophils, pubmed-meshheading:10444614-Female, pubmed-meshheading:10444614-Forced Expiratory Volume, pubmed-meshheading:10444614-Humans, pubmed-meshheading:10444614-Inflammation, pubmed-meshheading:10444614-Lung Volume Measurements, pubmed-meshheading:10444614-Male, pubmed-meshheading:10444614-Methacholine Chloride, pubmed-meshheading:10444614-Middle Aged, pubmed-meshheading:10444614-Plethysmography, pubmed-meshheading:10444614-Residual Volume, pubmed-meshheading:10444614-Respiration, pubmed-meshheading:10444614-Sputum
pubmed:year
1999
pubmed:articleTitle
Airway responsiveness to methacholine: effects of deep inhalations and airway inflammation.
pubmed:affiliation
Cattedra di Fisiopatologia Respiratoria, Dipartimento di Scienze Motorie e Riabilitative, Università di Genoa, 16132 Genoa, Italy. brusasco@dism.unige.it
pubmed:publicationType
Journal Article, Clinical Trial, Research Support, Non-U.S. Gov't