AGT and chronic obstructive pulmonary disease: In addition, angiotensin II (Ang II) produced by the activation of ACE can not only promote the proliferation of blood vessels, cause vasoconstriction, increase blood pressure, and regulate water and salt metabolism (sodium retention and potassium excretion) but also is a strong proinflammatory factor [5, 12], which can also cause and aggravate COPD in the process of inflammation promotion.