Arterial blood gas analysis in BLM-induced pulmonary fibrosis. Rats were administered saline or NNAV orally 4 days prior to BLM and continued until to the end of experiment. Arterial blood was collected in the syringe and sealed. Key indicators of blood gas testing including power of hydrogen (pH, A), lactic acid (B), partial pressure of carbon dioxide (PCO2, C), partial pressure of oxygen (PO2, D), oxygen saturation (SO2, E) were measured. *P<0.05, BLM group compared to control group; #P<0.05, NNAV-treated groups compared to BLM group. N =10 per group.