| Autor: |
Joad JP; Department of Pediatrics, School of Medicine; University of California at Davis, Davis, California, 95616, USA. jesse.joad@ucdmc.ucdavis.edu, Kott KS, Bric JM, Peake JL, Pinkerton KE |
| Jazyk: |
angličtina |
| Zdroj: |
Toxicology and applied pharmacology [Toxicol Appl Pharmacol] 2009 Feb 01; Vol. 234 (3), pp. 339-44. Date of Electronic Publication: 2008 Nov 20. |
| DOI: |
10.1016/j.taap.2008.10.018 |
| Abstrakt: |
Infants exposed to second hand smoke (SHS) experience more problems with wheezing. This study was designed to determine if perinatal SHS exposure increases intrinsic and/or in vivo airway responsiveness to methacholine and whether potential structural/cellular alterations in the airway might explain the change in responsiveness. Pregnant rhesus monkeys were exposed to filtered air (FA) or SHS (1 mg/m(3) total suspended particulates) for 6 h/day, 5 days/week starting at 50 days gestational age. The mother/infant pairs continued the SHS exposures postnatally. At 3 months of age each infant: 1) had in vivo lung function measurements in response to inhaled methacholine, or 2) the right accessory lobe filled with agarose, precision-cut to 600 mum slices, and bathed in increasing concentrations of methacholine. The lumenal area of the central airway was determined using videomicrometry followed by fixation and histology with morphometry. In vivo tests showed that perinatal SHS increases baseline respiratory rate and decreases responsiveness to methacholine. Perinatal SHS did not alter intrinsic airway responsiveness in the bronchi. However in respiratory bronchioles, SHS exposure increased airway responsiveness at lower methacholine concentrations but decreased it at higher concentrations. Perinatal SHS did not change eosinophil profiles, epithelial volume, smooth muscle volume, or mucin volume. However it did increase the number of alveolar attachments in bronchi and respiratory bronchioles. In general, as mucin increased, airway responsiveness decreased. We conclude that perinatal SHS exposure alters in vivo and intrinsic airway responsiveness, and alveolar attachments. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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