Abstract |
The induction of lung injury and the development of airway hyperresponsiveness (AHR) by exposure to hexamethylene diisocyanate (HDI) were studied in a guinea pig model of occupational lung diseases. In addition to an unexposed control group of 16 guinea pigs (A), two groups (B, C) of 8 animals inhaled HDI atmospheres in the range of the threshold limit value (TLV) of 10 ppb for 6 h/day on 5 days/week over a period of 8 weeks. Airway responses to aerosols of 0.125, 0.25, 0.5, 1.0 and 2.0% acetylcholine (ACH) were measured in exposed as well as in unexposed animals. Basal values of respiratory mechanical and cardiovascular parameters were not significantly altered after 8 weeks of HDI inhalation (group B). Furthermore, additional acute challenge by 10 ppb HDI for a period of 60 min, performed under continuous registration of respiratory and cardiovascular parameters, did not cause any significant changes in functional parameters. After 8 weeks of HDI exposure, the amplitude of airway constriction as a response to 2.0% ACH, indicated by the changes in dynamic elastance (Edyn) rose significantly to almost 5 times the ACH response in group A(p < 0.0005). In group C of 8 guinea pigs, ACH response was evaluated after a latency period of 8 weeks. In this group, changes of airway responsiveness to ACH were significantly smaller than in group B without a latency period. They were comparable to those of group A. In summary, HDI-induced airway hyperresponsiveness to ACH in the guinea pig is reversible within 8 weeks of HDI avoidance. It is assumed that the augmented airway responsiveness indicates an increased risk of developing isocyanate-induced obstructive lung diseases.
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Authors | W Marek, T Mensing, F Riedel, N Viso, B Marczynski, X Baur |
Journal | Respiration; international review of thoracic diseases
(Respiration)
Vol. 64
Issue 1
Pg. 35-44
( 1997)
ISSN: 0025-7931 [Print] Switzerland |
PMID | 9044473
(Publication Type: Comparative Study, Journal Article)
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Chemical References |
- Aerosols
- Cyanates
- Isocyanates
- 1,6-hexamethylene diisocyanate
- Acetylcholine
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Topics |
- Acetylcholine
(administration & dosage, toxicity)
- Administration, Inhalation
- Aerosols
(administration & dosage)
- Animals
- Bronchial Hyperreactivity
(chemically induced, physiopathology)
- Cyanates
(administration & dosage, toxicity)
- Disease Models, Animal
- Dose-Response Relationship, Drug
- Follow-Up Studies
- Guinea Pigs
- Hemodynamics
(drug effects)
- Isocyanates
- Lung Diseases, Obstructive
(chemically induced)
- Maximum Allowable Concentration
- Occupational Diseases
(chemically induced)
- Remission, Spontaneous
- Respiratory Function Tests
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