Expression of endothelin-1 in the lungs of patients with pulmonary hypertension

N Engl J Med. 1993 Jun 17;328(24):1732-9. doi: 10.1056/NEJM199306173282402.

Abstract

Background: Pulmonary hypertension is characterized by an increase in vascular tone or an abnormal proliferation of muscle cells in the walls of small pulmonary arteries. Endothelin-1 is a potent endothelium-derived vasoconstrictor peptide with important mitogenic properties. It has therefore been suggested that endothelin-1 may contribute to increases in pulmonary arterial tone or smooth-muscle proliferation in patients with pulmonary hypertension. We studied the sites and magnitude of endothelin-1 production in the lungs of patients with various causes of pulmonary hypertension.

Methods: We studied the distribution of endothelin-1-like immunoreactivity (by immunocytochemical analysis) and endothelin-1 messenger RNA (by in situ hybridization) in lung specimens from 15 control subjects, 11 patients with plexogenic pulmonary arteriopathy (grades 4 through 6), and 17 patients with secondary pulmonary hypertension and pulmonary arteriopathy of grades 1 through 3.

Results: In the controls, endothelin-1-like immunoreactivity was rarely seen in vascular endothelial cells. In the patients with pulmonary hypertension, endothelin-1-like immunoreactivity was abundant, predominantly in endothelial cells of pulmonary arteries with medial thickening and intimal fibrosis. Likewise, endothelin-1 messenger RNA was increased in the patients with pulmonary hypertension and was expressed primarily at sites of endothelin-1-like immunoreactivity. There was a strong correlation between the intensity of endothelin-1-like immunoreactivity and pulmonary vascular resistance in the patients with plexogenic pulmonary arteriopathy, but not in those with secondary pulmonary hypertension.

Conclusions: Pulmonary hypertension is associated with the increased expression of endothelin-1 in vascular endothelial cells, suggesting that the local production of endothelin-1 may contribute to the vascular abnormalities associated with this disorder.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Endothelins / biosynthesis*
  • Endothelium, Vascular / metabolism
  • Female
  • Humans
  • Hypertension, Pulmonary / metabolism*
  • Hypertension, Pulmonary / pathology
  • Hypertension, Pulmonary / physiopathology
  • In Situ Hybridization
  • Lung / blood supply
  • Lung / metabolism*
  • Male
  • Middle Aged
  • RNA, Messenger / analysis
  • Vascular Resistance

Substances

  • Endothelins
  • RNA, Messenger