Moreover previous studies reported that AGT could interact with TGF-β1 to promote fibrogenesis of Lung [18], in addition, there were also reports on the possible association between angiotensin-converting enzyme and angiotensin type I receptor polymorphisms and the risk of the developing BPD [19], but little attention has been directed to the AGT mediated physiologic pathways which is involved in the development of BPD. Here, AGT is linked to bronchopulmonary dysplasia.