In PAH, ETB Receptors Located on the Smooth Muscle Cell Become Pathogenic Mediators*
*Statements are based on observations reported from in vitro or animal trials. The clinical significance in humans is unknown.
Receptor Type
Healthy Vessel
Activity1-2
Diseased Vessel
Activity2-5
ETB
Vasodilation
Cell proliferation
Vasoconstriction
Inflammation
Fibrosis
Hypertrophy
ETA
Vasoconstriction
Cell proliferation
Vasoconstriction
Inflammation
Blockade of ETA and ETB Receptors Is Critical*
*Statements are based on observations reported from in vitro or animal trials. The clinical significance in humans is unknown.
REFERENCES
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Goraca A. New views on the role of endothelin. Endocr Regul. 2002;36:161–167.
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Kedzierski RM, Yanagisawa M. Endothelin system: the double-edged sword in health and disease. Annu Rev Pharmacol Toxicol. 2001;41:851–876.
3. 
Davie N, Haleen SJ, Upton PD, et al. ET(A) and ET(B) receptors modulate the proliferation of human pulmonary artery smooth muscle cells. Am J Respir Crit Care Med. 2002;165:398–405.
4. 
Kim NH, Rubin LJ. Endothelin in health and disease: endothelin receptor antagonists in the management of pulmonary artery hypertension. J Cardiovasc Pharmacol Ther. 2002;7:9–19.
5. 
Rae GA, Henriques MGMO. Endothelins in inflammation. In: Said SI, ed. Proinflammatory and Antiinflammatory Peptides. New York: Marcel Dekker Inc; 1998:163–202.
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