Sterner-Kock A, Vesely K R, Stovall M Y, Schelegle E S, Green J F, Hyde D M
Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis, 95616, USA.
Am J Respir Crit Care Med. 1996 Jan;153(1):436-43. doi: 10.1164/ajrccm.153.1.8542155.
To test the hypothesis that lung sensory C fibers protect the small distal airways and alveoli from oxidant injury, we compared the effects of inhalation of ozone (1 ppm) or filtered air for 8 h on lung injury and lung inflammation in four groups of rats: (1) normal rats exposed to filtered air; (2) normal rats exposed to ozone; (3) rats treated as neonates with capsaicin (50 mg/kg, intraperitoneally) and subsequently exposed to filtered air; and (4) rats treated as neonates with capsaicin and subsequently exposed to ozone. All rats were allowed to recover in filtered air for 0, 4, 16, and 40 h before necropsy. Rats exposed to filtered air (Groups 1 and 3) showed normal airway and parenchyma structure. Normal untreated rats exposed to ozone showed a random distribution of mild, interstitial inflammatory changes and epithelial necrosis of bronchi and bronchiolar epithelium. However, rats treated with capsaicin and subsequently exposed to ozone demonstrated severe acute interstitial inflammation and epithelial coagulate necrosis in all airways, especially in small, peripheral airways and parenchyma; all of these changes were statistically significant. These findings support our hypothesis that lung sensory C fibers protect the distal airways from oxidant injury during acute ozone inhalation.
为了验证肺感觉C纤维可保护小的远端气道和肺泡免受氧化损伤这一假说，我们比较了四组大鼠吸入臭氧（1 ppm）或过滤空气8小时对肺损伤和肺部炎症的影响：（1）暴露于过滤空气的正常大鼠；（2）暴露于臭氧的正常大鼠；（3）新生期用辣椒素（50 mg/kg，腹腔注射）处理后再暴露于过滤空气的大鼠；（4）新生期用辣椒素处理后再暴露于臭氧的大鼠。在尸检前，所有大鼠在过滤空气中恢复0、4、16和40小时。暴露于过滤空气的大鼠（第1组和第3组）气道和实质结构正常。未处理的正常大鼠暴露于臭氧后，支气管和细支气管上皮出现轻度、间质性炎症变化和上皮坏死，呈随机分布。然而，用辣椒素处理后再暴露于臭氧的大鼠在所有气道，尤其是小的外周气道和实质中出现严重的急性间质性炎症和上皮凝固性坏死；所有这些变化均具有统计学意义。这些发现支持了我们的假说，即肺感觉C纤维在急性吸入臭氧期间可保护远端气道免受氧化损伤。
