Overexpression of angiotensin AT1 receptor transgene in the mouse myocardium produces a lethal phenotype associated with myocyte hyperplasia and heart block.

Published

Journal Article

Previous studies have suggested that angiotensin II (Ang II) modulates cardiac contractility, rhythm, metabolism, and structure. However, it is unclear whether the cardiac effects are due to direct actions of Ang II on the myocardium or if they are due to secondary effects mediated through the hemodynamic actions of Ang II. In this study, we used the alpha-myosin heavy chain (alphaMHC) promoter to generate transgenic mice overexpressing angiotensin II type 1 (AT1a) receptor selectively in cardiac myocytes. The specificity of transgene expression in the transgenic offspring was confirmed by radioligand binding studies and reverse transcription-PCR. The offspring displayed massive atrial enlargement with myocyte hyperplasia at birth, developed significant bradycardia with heart block, and died within the first weeks after birth. Thus, direct activation of AT1 receptor signaling in cardiac myocytes in vivo is sufficient to induce cardiac myocyte growth and alter electrical conduction.

Full Text

Duke Authors

Cited Authors

  • Hein, L; Stevens, ME; Barsh, GS; Pratt, RE; Kobilka, BK; Dzau, VJ

Published Date

  • June 10, 1997

Published In

Volume / Issue

  • 94 / 12

Start / End Page

  • 6391 - 6396

PubMed ID

  • 9177228

Pubmed Central ID

  • 9177228

International Standard Serial Number (ISSN)

  • 0027-8424

Digital Object Identifier (DOI)

  • 10.1073/pnas.94.12.6391

Language

  • eng

Conference Location

  • United States