Endothelin-1 and eNOS expression in pulmonary aterioles of patients with congenital heart diseases with pulmonary hypertension

AIM: To clarify the role of eNOS and ET-1 in development of pulmonary hypertension (PH) associated with congenital heart diseases. METHODS: 40 patients were randomly divided into three groups: severe or moderate PH group (group A, 12 cases), slight PH group (group B, 14 cases) and normal group (group C, 14 cases). ET-1 and eNOS were examined by using the technique of immunohistochemistry. RESULTS: ① Plasma ET-1 concentration was significantly higher in group A and B than that in group C (P<0.01). Serum NO concentration in group A and B was significantly lower than that in group C (P<0.01). ② The proliferation of medial smooth muscle cells and collagenous fibers of pulmonary arteriole in patients with PH were observed by electron microscopy. ③ ET-1 in pulmonary arteriole was significantly higher in group A and group B than that in group C (P<0.01). eNOS in pulmonary arteriole was significantly lower in group A and group B than that in group C (P<0.01). CONCLUSION: ET-1 and eNOS may play an important role in the pathogenesis of PH.