Hoffman A M, Mazan M R, Ellenberg S
Department of Medicine, School of Veterinary Medicine, Tufts University, Grafton, MA 01536, USA.
Am J Vet Res. 1998 Feb;59(2):176-81.
To correlate indices of airway reactivity to bronchoalveolar lavage (BAL) fluid cytologic features in horses with a recent decline in exercise tolerance.
20 actively working horses from 2 to 24 years old.
Bronchoalveolar lavage fluid samples were obtained and analyzed. Forced oscillatory mechanics (1-7 Hz) technique was used for measurements of total respiratory system resistance (RRS), compliance (CRS), and resonant frequency (fres). Changes in RRS (1 Hz) during histamine challenge were used to generate histamine dose-response curves, from which the provocative concentrations that evoked a 75 or 100% increase in baseline RRS (PCRRS75 and PCRRS 100, respectively) were determined. Age, sex, baseline lung mechanics, and BAL cytologic findings were correlated with PCRRS75 and PCRRS100.
No horse of the study had clinical signs or history of obstructive pulmonary disease or increased percentage (> 7%) of neutrophils in bronchoalveolar lavage fluid samples. Mean (+/- SEM) RRS, CRS, and fres were 0.67 +/- 0.06 cm of H2O/L/s, 0.52 +/- 0.04 L/cm H2O, and 2.46 +/- 0.02 Hz, respectively. There was no correlation between age or sex, and RRS, CRS, fres, PCRRS75, or PCRRS100. There was a significant correlation (rs = -0.78, P < 0.001) between percentage of BAL fluid mast cells and PCRRS75 or PCRRS100, but correlation with other cell types and indices of airway reactivity were not observed.
The strong association between mast cell percentage in BAL fluid and airway reactivity in this group suggests that mast cell products may contribute to bronchospasm, airway wall thickening, and/or loss of elastic recoil, which underlie airway hyperreactivity. Alternatively, mast cells may contribute to nonspecific airway reactivity in horses through unknown mechanisms.
将气道反应性指标与近期运动耐量下降的马匹支气管肺泡灌洗（BAL）液细胞学特征进行关联分析。
20匹年龄在2至24岁之间的现役工作马。
获取并分析支气管肺泡灌洗液样本。采用强迫振荡力学（1 - 7赫兹）技术测量总呼吸系统阻力（RRS）、顺应性（CRS）和共振频率（fres）。组胺激发试验期间RRS（1赫兹）的变化用于生成组胺剂量 - 反应曲线，由此确定引起基线RRS增加75%或100%的激发浓度（分别为PCRRS75和PCRRS100）。将年龄、性别、基线肺力学和BAL细胞学结果与PCRRS75和PCRRS100进行关联分析。
本研究中没有一匹马有阻塞性肺疾病的临床症状或病史，支气管肺泡灌洗液样本中中性粒细胞百分比也未增加（>7%）。平均（±标准误）RRS、CRS和fres分别为0.67±0.06厘米水柱/升/秒、0.52±0.04升/厘米水柱和2.46±0.02赫兹。年龄或性别与RRS、CRS、fres、PCRRS75或PCRRS100之间无相关性。BAL液肥大细胞百分比与PCRRS75或PCRRS100之间存在显著相关性（rs = -0.78，P < 0.001），但未观察到与其他细胞类型及气道反应性指标的相关性。
该组中BAL液肥大细胞百分比与气道反应性之间的强关联表明，肥大细胞产物可能导致支气管痉挛、气道壁增厚和/或弹性回缩丧失，这些是气道高反应性的基础。或者，肥大细胞可能通过未知机制导致马匹非特异性气道反应性。
