Frank L, Roberts R J
J Appl Physiol Respir Environ Exerc Physiol. 1979 Sep;47(3):577-81. doi: 10.1152/jappl.1979.47.3.577.
Small dosages of endotoxin (100--500 micrograms/kg) provide significant protection against the acute manifestations of pulmonary O2 toxicity and lethality. Ninety-seven percent of endotoxin-treated adult rats survived a 72-h exposure to greater than or equal to 95% O2 with mimimal lung changes, compared to 32% of control animals (P less than 0.01). Exposure to greater than or equal to 95% O2 for 7 days resulted in a 20% survival rate in untreated control rats vs. 98% survival in endotoxin-treated rats (P LESS THan 0.01). Histological evaluation of lung from survivors revealed substantially less collagen and reticular fiber deposition in the endotoxin-treated animal lungs. Endotoxin treatment was associated with increased activity of the protectant antioxidant enzyme systems of the lung in an apparent dose-response manner. Endotoxin's protective activity against O2 toxicity does not appear to depend on an initial toxic insult to the lung like with alpha-naphthylthiourea, oleic acid, or alloxan treatment. The data support a protective role for endotoxin against the acute and the more chronic manifestations of O2-induced pulmonary injury.
小剂量内毒素（100 - 500微克/千克）能显著预防肺氧中毒和致死的急性表现。与32%的对照动物相比，97%接受内毒素治疗的成年大鼠在暴露于大于或等于95%氧气72小时后存活，且肺部变化极小（P < 0.01）。暴露于大于或等于95%氧气7天，未治疗的对照大鼠存活率为20%，而内毒素治疗的大鼠存活率为98%（P < 0.01）。对存活者肺部的组织学评估显示，内毒素治疗的动物肺部胶原蛋白和网状纤维沉积明显减少。内毒素治疗与肺部保护性抗氧化酶系统活性以明显的剂量反应方式增加有关。内毒素对氧中毒的保护活性似乎不像用α-萘基硫脲、油酸或四氧嘧啶治疗那样依赖于对肺部的初始毒性损伤。这些数据支持内毒素对氧诱导的肺损伤的急性和更慢性表现具有保护作用。
