Busch R H, Buschbom R L, Cannon W C, Lauhala K E, Miller F J, Graham J A, Smith L G
Environ Res. 1984 Apr;33(2):454-72. doi: 10.1016/0013-9351(84)90042-2.
Rats and guinea pigs, pretreated with intratracheally administered elastase or saline, were exposed to 1.03 mg/m3 (NH4)2SO4; MMAD, 0.42 micron. Identically treated controls were sham exposed. Measurements and evaluation of structural changes were conducted using morphometric techniques on SEM photographs and by applying subjective ratings. Pathology studies were conducted by light and electron microscopy. All examination methods confirmed elastase-induced emphysema, which was aggravated by (NH4)2SO4 exposure in the rat. Ammonium sulfate exposure of saline-treated animals produced measurable degrees of enlargement of alveoli, and alveolar ducts and sacs. Electron microscopy revealed increased interstitial collagen in affected lung areas of elastase-treated, (NH4)2SO4-exposed animals. Alveolar-pore size was significantly increased in elastase-treated animals (control and exposed) but not in saline-treated, exposed animals. The data suggest a possible difference between elastase and (NH4)2SO4 in the mechanisms responsible for the increased diameter of alveolar structures. Hypertrophy and hyperplasia of nonciliated epithelial cells of the small airways and of the Type II alveolar cells were observed in otherwise untreated guinea pigs exposed to (NH4)2SO4 but not in elastase-treated guinea pigs, nor in any of the rats.
用气管内注射弹性蛋白酶或生理盐水预处理的大鼠和豚鼠，暴露于1.03毫克/立方米的硫酸铵（MMAD为0.42微米）环境中。相同处理的对照组进行假暴露。使用形态计量技术对扫描电子显微镜照片进行测量和结构变化评估，并进行主观评分。通过光学显微镜和电子显微镜进行病理学研究。所有检查方法均证实弹性蛋白酶可诱发肺气肿，在大鼠中，硫酸铵暴露会加重这种肺气肿。硫酸铵暴露于经生理盐水处理的动物会使肺泡、肺泡管和肺泡囊出现可测量程度的增大。电子显微镜显示，在经弹性蛋白酶处理且暴露于硫酸铵的动物的受影响肺区域，间质胶原增加。弹性蛋白酶处理的动物（对照组和暴露组）的肺泡孔尺寸显著增加，但经生理盐水处理且暴露的动物则未增加。数据表明，弹性蛋白酶和硫酸铵在导致肺泡结构直径增加的机制上可能存在差异。在未接受其他处理但暴露于硫酸铵的豚鼠中，观察到小气道的无纤毛上皮细胞和II型肺泡细胞肥大及增生，但在经弹性蛋白酶处理的豚鼠以及所有大鼠中均未观察到这种情况。
