Evaluation of leukotriene B-4 in the canine exhaled breath: Standardization of a technique of sample collection

摘要

Several techniques are used to define the degree of disease of the bronchopulmonary apparatus. The most commonly employed techniques include thorax radiography, bronchoscopy, examination of tracheobronchial secretions and, more recently, identification of inflammatory targets (hydrogen peroxide, nitric oxide, prostaglandins and leukotrienes) (Loukides et al., 1998; Heard et al., 1999). These latter substances can be extracted using bronchoalveolar lavage. However, a major limitation of this technique is related to the degree of dilution of the substance in the lavage. In addition, this technique allows for liberation of the chemical mediator of inflammation by the cellular component of the sample (Hawkins and Berry, 1999). For this reason, the evaluation of leukotrienes from expired breath has partially replaced analysis of bronchoalveolar lavage in human medicine (Scheideler et al, 1993; Becher et al., 1997). In veterinary medicine this technique has been applied to cattle experimentally infected with specific viruses and bacteria (Reihnold et al., 1997). The aim of our study was to standardize the techniques of collection of exhaled breath in healthy dogs and in dogs affected by respiratory diseases, in order to extract leukotriene B_4 by enzymatic immumoassay (EIA) technique.