Considering the pathophysiological importance of fibroblast activation in pulmonary fibrosis [4, 28, 29] and the above-mentioned reports about CNP and cardiac fibroblasts [25, 26], we hypothesized that the anti-fibrotic and anti-inflammatory effects of exogenous CNP against BLM-induced pulmonary fibrosis were exerted at least in part by the effect of CNP on pulmonary fibroblasts. This evidence concerns the gene CNP and pulmonary fibrosis.