Lung angiotensin receptor binding characteristics during the development of monocrotaline-induced pulmonary hypertension

Lisa Cassis, Ujjwala Shenoy, David Lipke, Jennifer Baughn, Michael Fettinger, Mark Gillespie

Research output: Contribution to journalArticlepeer-review

19 Scopus citations


Alterations in lung angiotensin converting enzyme (ACE) activity in monocrotaline (MCT)induced pulmonary hypertension in rats have suggested a pathophysiologic role for angiotensin II (AII) in pulmonary vascular remodeling. ACE inhibitors suppress MCT-induced pulmonary hypertension; however, losartan, an angiotensin type 1 (AT1) receptor antagonist, was without impact. The present study examined AII receptor binding characteristics by radioligand binding during the development of MCT-induced pulmonary hypertension Saturation binding isotherms for [125I]AII binding to membrane preparations from rat lung were performed at 4, 10, and 21 days following a single injection of MCT (60 mg/kg) or saline vehicle. Right ventricular hypertrophy, an index of pulmonary hypertension, increased at 21 days post-MCT. Saturation binding isotherms revealed a single, high affinity site for [125I]AII binding in lung membranes from MCT-treated and control rats, with no change in receptor affinity or density during the development of pulmonary hypertension. Competition displacement binding demonstrated that the AT1 receptor predominates in lung membranes from control rats, with no alterations in AII receptor subtype distribution following MCT treatment. In summary, these results suggest that the AT1 receptor subtype predominates in rat lung and does not contribute to the development of MCT induced pulmonary hypertension.

Original languageEnglish
Pages (from-to)27-31
Number of pages5
JournalBiochemical Pharmacology
Issue number1
StatePublished - Jul 1 1997

Bibliographical note

Funding Information:
The authors wish to acknowledge DuPont-Merck Pharmaceuticals for losartan, ad Parke-Davis PhaImaceuticals for PDl233 19. This work was supported by K04HL02742, HL36495, and HL43831.


  • Angiotensin receptor
  • Binding
  • Monocrotaline
  • Pulmonary hypertension

ASJC Scopus subject areas

  • Biochemistry
  • Pharmacology


Dive into the research topics of 'Lung angiotensin receptor binding characteristics during the development of monocrotaline-induced pulmonary hypertension'. Together they form a unique fingerprint.

Cite this