模拟月尘致大鼠肺脏急性损伤病理学变化

Pathological Changes of Acute Pulmonary Injury in Rats Induced by Tracheal Perfusion of Lunar Soil Simulant

目的探讨模拟月尘(lunar soil simulant,LSS)对大鼠肺脏急性损伤的病理学改变。方法采用粒径在5μm以下的CAS-1模拟月壤作为真实月壤的替代物。用无菌生理盐水配制模拟月尘混悬液。通过气管滴注染毒法制备模拟月尘的动物模型,同时与PM2.5及生理盐水组对照,观察染尘不同时期大鼠肺脏的超微结构变化。结果 LSS高剂量组(灌注量1 m L,含7 mg LSS)4 h图片可见肺泡间隔增厚和中性粒细胞浸润;24 h图片可见肺泡间隔增厚和血管内中性粒细胞浸润,以及血管和支气管周围炎。LSS低剂量组(灌注量1 m L,含0.7 mg LSS)4 h图片未见组织明显病变;24 h图片可见肺泡隔轻微增厚,支气管周围有中性粒细胞浸润但比LSS高剂量组轻。PM2.5组4 h和24 h图片均未观察到炎症、水肿。结论 LSS可能具有比PM2.5更强的肺毒性,可引起机体肺实质损伤,产生炎症性病变。

Objective To investigate the pathological changes of acute injury induced by lunar soil simulant （LSS） in rats. Methods Fine lunar soil simulant（ CAS-1 lunar dust analog）with the diameter size under 5 μm suspended in saline was intratracheally instilled into Wistar rats （ tracheal perfusion 1 mL with 7 mg and 0.7 mg respectively）. At the same time, compared with PM2.5 and normal saline group, the ultrastructural chan- ges of lung in rats during different periods were observed. Results The lungs of LSS high dose group showed alveolar septal thickening and neutrophil infiltration after 4 h tracheal perfusion, but no obvious pathological changes were visible in LSS low dose group. The lungs of LSS high dose group showed septal thickening, neu- trophil infiltration and inflammation after 24 h. But slight pathological changes were visible in LSS low dose group after 24 h. There was no evidence of visible inflammation or edema in PM2.5 group. Conclusion LSS may have stronger lung toxicity than PM2.5, which can cause lung parenchymal injury and inflammatory le- sions.