Becker A B, Hershkovich J, Simons F E, Simons K J, Lilley M K, Kepron M W
Department of Pediatrics, Faculty of Medicine, University of Manitoba, Winnipeg, Canada.
J Appl Physiol (1985). 1989 Jun;66(6):2691-7. doi: 10.1152/jappl.1989.66.6.2691.
We studied dogs neonatally sensitized to ragweed and their littermate controls at 4, 6, 8, 10, 12, and 15 mo of age. Acute allergic airway response to inhalation of ragweed in the sensitized dogs was marked (greater than 12-fold increase from base line) and reproducible at all times. Nonallergic airway responsiveness, measured as the concentration of acetylcholine required to increase airway resistance by 5 cmH2O.l-1.s (PC5), increased in sensitized and decreased in nonsensitized dogs from 4 to 15 mo of age (P less than 0.01). Before antigen, at 12 and 15 mo, sensitized dogs were significantly (P less than 0.05) more responsive to acetylcholine than controls. Six hours after antigen, sensitized dogs were 11-fold more responsive (P less than 0.005) than controls at those times. More eosinophils and mast cells and fewer macrophages (P less than 0.05) were present in bronchoalveolar lavage (BAL) from 12- and 15-mo-old sensitized dogs than their controls. BAL fluid histamine was higher (P less than 0.05) in sensitized than control dogs. Regression analysis revealed r = -0.75 (P = 0.003) between BAL mast cells and PC5 in sensitized dogs and R2 = 0.89 for PC5 and BAL mast cells, macrophages, and eosinophils. Neonatally sensitized dogs represent an excellent animal model in which to study the pathophysiology of asthma.
我们研究了新生期对豚草致敏的犬及其同窝对照犬在4、6、8、10、12和15月龄时的情况。致敏犬吸入豚草后急性过敏气道反应明显（比基线增加超过12倍），且在所有时间均可重现。以使气道阻力增加5 cmH2O·l-1·s所需的乙酰胆碱浓度（PC5）衡量的非过敏性气道反应性，在4至15月龄时，致敏犬增加，未致敏犬降低（P<0.01）。在抗原刺激前，12和15月龄时，致敏犬对乙酰胆碱的反应性显著高于对照犬（P<0.05）。抗原刺激6小时后，致敏犬在这些时间点的反应性比对照犬高11倍（P<0.005）。12和15月龄致敏犬支气管肺泡灌洗（BAL）中的嗜酸性粒细胞和肥大细胞更多，巨噬细胞更少（P<0.05）。致敏犬的BAL液组胺高于对照犬（P<0.05）。回归分析显示，致敏犬BAL中的肥大细胞与PC5之间的r = -0.75（P = 0.003），PC5与BAL中的肥大细胞、巨噬细胞和嗜酸性粒细胞之间的R2 = 0.89。新生期致敏犬是研究哮喘病理生理学的优良动物模型。
