The important role of NOS in whole-body homeostasis has been revealed in triple nNOS/eNOS/iNOS-null mice that exhibit renal (nephrogenic diabetes insipidus and pathological renal remodeling), lung (accelerated pulmonary fibrosis), and bone (increased bone mineral density and bone turnover) abnormalities [11]. Here, NOS1 is linked to pulmonary fibrosis.