EC-specific CNP or GC-B conditional knockout (CNP ecKO or GC-B ecKO) mice, but not smooth muscle cell-specific GC-B conditional knockout (GC-B smcKO) mice, show more severe PH and greater expression of Edn1, Il6, Ccl2 and Tgfb1 mRNAs than their genetic controls in PAH models. Here, EDN1 is linked to pulmonary arterial hypertension.