AGT and pulmonary arterial hypertension: Interestingly, DUSP5 expression has been shown to be upregulated by angiotensin II (ANG II) in primary rat aortic VSMCs, [23] but DUSP5 serves as a negative regulator of ANG-II-mediated cell proliferation in VSMCs from de-identified patients with pulmonary arterial hypertension [24].