Delaunois A, Segura P, Montaño L M, Vargas M H, Ansay M, Gustin P
Department of Pharmacology-Toxicology, Faculty of Veterinary Medicine, Université de Liège, Belgium.
Toxicol Appl Pharmacol. 1998 May;150(1):58-67. doi: 10.1006/taap.1998.8397.
The effects of rabbit exposure to ozone (O3)(0.4 ppm for 4 h) on pulmonary mechanical properties and hemodynamics have been investigated on the isolated perfused lung model. Tracheal pressure, airflow, and tidal volume were measured in order to calculate lung resistance (RL) and dynamic compliance (Cdyn). Using the arterial/venous/double occlusion method, the total pressure gradient (deltaPT) was partitioned into four components (arterial, pre-, postcapillary and venous). Dose-response curves to acetylcholine (ACh), substance P (SP), and histamine were constructed in lungs isolated from rabbits immediately or 48 h after air or O3 exposure O3 induced a significant increase in the baseline value of deltaPt, more markedly 48 h after the exposure. Immediately after the exposure, O3 partly inhibited the ACh-, SP-, and histamine-induced decreases in Cdyn and increases in RL. This inhibitory effect was still in part present 48 h after O3 treatment. In the groups studied immediately after exposure, O3 did not significantly modify the ACh-, SP-, and histamine-induced vasoconstriction. Forty-eight hours after exposure, O3 induced a contractile response to ACh and SP in the arterial segment but decreased the response to histamine. We conclude that O3 can induce direct vascular constriction. Directly, but also 48 h after exposure, O3 can inhibit the ACh-, SP-, and histamine-induced changes in lung mechanical properties. Ozone can also induce some changes in the intensity and in the location of the vascular responses to ACh, SP, and histamine.
在离体灌注肺模型上研究了家兔暴露于臭氧（O₃）（0.4 ppm，4小时）对肺力学特性和血流动力学的影响。测量气管压力、气流和潮气量，以计算肺阻力（RL）和动态顺应性（Cdyn）。采用动脉/静脉/双阻断法，将总压力梯度（deltaPT）分为四个部分（动脉、毛细血管前、毛细血管后和静脉）。在空气或O₃暴露后立即或48小时从家兔分离的肺中构建对乙酰胆碱（ACh）、P物质（SP）和组胺的剂量反应曲线。O₃使deltaPt的基线值显著增加，暴露后48小时更明显。暴露后立即，O₃部分抑制ACh、SP和组胺诱导的Cdyn降低和RL增加。O₃处理后48小时，这种抑制作用仍部分存在。在暴露后立即研究的组中，O₃没有显著改变ACh、SP和组胺诱导的血管收缩。暴露后48小时，O₃在动脉段诱导对ACh和SP的收缩反应，但降低对组胺的反应。我们得出结论，O₃可诱导直接血管收缩。直接地，而且在暴露后48小时，O₃可抑制ACh、SP和组胺诱导的肺力学特性变化。臭氧还可诱导对ACh、SP和组胺的血管反应强度和位置发生一些变化。
