In the first series of experiments, we evaluated the effects of intratracheal administration of bleomycin (0.05 IU), a dose able to lead to pulmonary fibrosis 38 on PARP activity, and Figure 1 shows that PARylated protein levels, the products of PARP activity, were significantly increased in lung homogenates of mice treated with bleomycin. The gene discussed is PARP1; the disease is pulmonary fibrosis.