Silbaugh S A, Mauderly J L, Macken C A
J Toxicol Environ Health. 1981 Jul-Aug;8(1-2):31-45. doi: 10.1080/15287398109530048.
Hartley guinea pigs were exposed for 1 h to either NO2 gas of H2SO4 aerosol and examined for changes in airway responsiveness to inhaled histamine. Concentrations ranged from 7 to 146 ppm NO2 and 4 to 40 mg/m3 H2SO4. One group of animals exposed to filtered air served as controls. Histamine challenges were performed on unanesthetized animals 2 h before pollutant or air exposure (baseline) and 10 min and 2 and 19 h after exposure. No2-exposed animals had increased histamine sensitivities 10 min after exposure, and the magnitude of the increase was directly dependent on the NO2 concentration. Most of the NO2-exposed animals demonstrated a dramatic return toward baseline values by 2 h after exposure; however, several animals had not returned to baseline by 19 h after exposure. Some animals exposed to H2SO4 developed severe labored breathing during exposure, and major increases in histamine sensitivity were observed only in those animals. These results suggest that both No2 and H2SO4 alter airway sensitivity to histamine, but apparently by different mechanisms. Changes produced by NO2 exposures appeared primarily concentration-dependent, while changes produced by H2SO4 exposures appeared related to dyspnea developed during exposure.
将哈特利豚鼠暴露于二氧化氮气体或硫酸气溶胶中1小时，然后检测其气道对吸入组胺反应性的变化。二氧化氮浓度范围为7至146 ppm，硫酸浓度范围为4至40 mg/m³。一组暴露于过滤空气中的动物作为对照。在污染物或空气暴露前2小时（基线）以及暴露后10分钟、2小时和19小时对未麻醉的动物进行组胺激发试验。暴露于二氧化氮的动物在暴露后10分钟组胺敏感性增加，且增加幅度直接取决于二氧化氮浓度。大多数暴露于二氧化氮的动物在暴露后2小时显示出急剧恢复至基线值；然而，一些动物在暴露后19小时仍未恢复到基线。一些暴露于硫酸的动物在暴露期间出现严重的呼吸困难，并且仅在这些动物中观察到组胺敏感性大幅增加。这些结果表明，二氧化氮和硫酸均会改变气道对组胺的敏感性，但显然是通过不同机制。二氧化氮暴露产生的变化主要表现为浓度依赖性，而硫酸暴露产生的变化似乎与暴露期间出现的呼吸困难有关。
