Pulmonary Endothelium-Bound Enzymes in the Normal and the Diseased Lung

  • S. E. Orfanos
  • A. Kotanidou
  • C. Roussos
Conference paper


The most intimai layer covering all blood vessels is composed of a single, continuous sheet of simple squamous epithelial cells of mesenchymal origin, which are called endothelial cells. Endothelial cells possess numerous important metabolic properties. In the human lung, endothelial cells constitute over 40% of all cell types and occupy an area with a surface of approximately 130 m2 [1]. The strategic location of the lungs, and the tremendous surface area of the pulmonary capillary endothelium allow the latter to filter the entire circulating blood volume before it enters the systemic circulation. Healthy pulmonary endothelium, among other features, promotes anti-aggregation and hemofluidity; synthesizes and/or degrades several hormones and vasoactive peptides such as angiotensin II, nitric oxide (NO), endothelins, and prostaglandins (regulating both pulmonary and systemic vascular tones); processes lipids; and interacts with blood components such as neutrophils, monocytes, and platelets [2, 3]. Consequently, the pulmonary endothelium is a major metabolic organ necessary for the adequate homeostasis of both the pulmonary and systemic circulations.


Angiotensin Converting Enzyme Acute Lung Injury Adult Respiratory Distress Syndrome Angiotensin Converting Enzyme Activity Pulmonary Endothelium 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • S. E. Orfanos
  • A. Kotanidou
  • C. Roussos

There are no affiliations available

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