| Autor: |
PIRIE, R. S., DIXON, P. M., COLLIE, D. D. S., McGORUM, B. C. |
| Zdroj: |
Equine Veterinary Journal; May2001, Vol. 33 Issue 3, p311-318, 8p |
| Abstrakt: |
Summary To investigate whether inhaled endotoxin contributes to airway inflammation and dysfunction in stabled horses, control (n = 6) and asymptomatic heaves (previously termed chronic obstructive pulmonary disease)-susceptible (n = 7) horses were given inhalation challenges with 20, 200 and 2000 μg of soluble Salmonella typhimurium Ra60 lipopolysaccharide (LPS). LPS inhalation induced a dose-dependent neutrophilic airway inflammatory response in both groups. Inhalation with 2000 μg of LPS also induced detectable lung dysfunction in the heaves group. LPS inhalation did not alter clinical score, tracheal secretion volume orairway reactivity in eithergroup. The no-response thresholds were lower for the heaves group (<20 μg for airway inflammation; 200 to 2000 μg for lung dysfunction) than for the control group (20 to 200 μg for airway inflammation; >2000 μg for lung dysfunction). To enable comparison of these threshold levels with airborne endotoxin concentrations in stables, horses also received a 5 h duration hay/straw challenge, during which the total and respirable airborne endotoxin concentrations were determined. Comparison of the effects of acute LPS inhalation and hay/straw challenges suggest that inhaled endotoxin is not the sole cause of heaves. However, it is likely that it contributes to airway inflammation, both in heaves horses in concert with other inhalants, and in normal horses when they are exposed to high levels in poor stable environments. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
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