The Function of ETB Receptors* in Pulmonary Arterial Hypertension (PAH)
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
Activity
Diseased Vessel
Activity
ETB
Vasodilation1,2
Cell proliferation4
Vasoconstriction7
Inflammation2,5
Fibrosis1,4
Hypertrophy6
ETA
Vasoconstriction2,3
Cell proliferation4
Vasoconstriction7
Inflammation2,5
Blockade of Endothelin Receptors May Provide Benefits*7
*Statements are based on observations reported from in vitro or animal trials.
The clinical significance in humans is unknown.
REFERENCES
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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. 
Goraca A. New views on the role of endothelin. Endocr Regul. 2002;36:161–167.
4. 
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.
5. 
Muller DN, Mervaala EM, Schmidt F, et al. Effect of bosentan on NF-kappaB, inflammation, and tissue factor in angiotensin II-induced end-organ damage. Hypertension. 2000;36:282–290.
6. 
Miyauchi T, Masaki T. Pathophysiology of endothelin in the cardiovascular system. Annu Rev Physiol. 1999;61:391–415.
7. 
Rich S, McLaughlin VV. Pulmonary hypertension. In: Libby P, Bonow RO, Mann DL, Zipes DE. Braunwald's Heart Disease. 2 vols. 8th ed. Philadelphia, PA: Saunders Elsevier; 2008:1883–1914.