TGFB1 and pulmonary fibrosis: Based on these points mentioned above, we used a rat model of pulmonary fibrosis stimulated by BLM instillation, treated with aminoguanidine (AG), an inhibitor of AGE formation by carbonyl-blocking [2], to explore whether AGE formation participates in BLM-induced pulmonary fibrosis, and whether it is involved in HSP47 expression and TGFβ signaling pathway.