Cardiac remodeling during and after renin-angiotensin system stimulation in Cyp1a1-Ren2 transgenic rats

Bart Fj Heijnen, Leonie Pj Pelkmans, Ah Jan Danser, Ingrid M Garrelds, John J Mullins, Jo Gr De Mey, Harry Aj Struijker-Boudier, Ben Ja Janssen

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

This study investigated renin-angiotensin system (RAS)-induced cardiac remodeling and its reversibility in the presence and absence of high blood pressure (BP) in Cyp1a1-Ren2 transgenic inducible hypertensive rats (IHR). In IHR (pro)renin levels and BP can be dose-dependently titrated by oral administration of indole-3-carbinol (I3C). Young (four-weeks old) and adult (30-weeks old) IHR were fed I3C for four weeks (leading to systolic BP >200 mmHg). RAS-stimulation was stopped and animals were followed-up for a consecutive period. Cardiac function and geometry was determined echocardiographically and the hearts were excised for molecular and immunohistochemical analyses. Echocardiographic studies revealed that four weeks of RAS-stimulation incited a cardiac remodeling process characterized by increased left ventricular (LV) wall thickness, decreased LV volumes, and shortening of the left ventricle. Hypertrophic genes were highly upregulated, whereas in substantial activation a fibrotic response was absent. Four weeks after withdrawal of I3C, (pro)renin levels were normalized in all IHR. While in adult IHR BP returned to normal, hypertension was sustained in young IHR. Despite the latter, myocardial hypertrophy was fully regressed in both young and adult IHR. We conclude that (pro)renin-induced severe hypertension in IHR causes an age-independent fully reversible myocardial concentric hypertrophic remodeling, despite a continued elevated BP in young IHR.
Original languageEnglish
JournalJournal of the Renin-Angiotensin-Aldosterone System
Volume15
Issue number1
Pages (from-to)69-81
ISSN1470-3203
DOIs
Publication statusPublished - Mar 2014

Keywords

  • Cyp1a1-Ren2 transgenic rat
  • Renin-angiotensin system
  • cardiac remodeling
  • fibrosis
  • heart failure
  • hypertrophy
  • Hypertension/pathology
  • Heart/physiopathology
  • Rats, Transgenic
  • Rats
  • Male
  • Renin-Angiotensin System/drug effects
  • Cytochrome P-450 CYP1A1/genetics
  • Renin/genetics
  • Indoles/pharmacology
  • Cardiomegaly/chemically induced
  • Animals
  • Myocardium/pathology
  • Aging

Fingerprint

Dive into the research topics of 'Cardiac remodeling during and after renin-angiotensin system stimulation in Cyp1a1-Ren2 transgenic rats'. Together they form a unique fingerprint.

Cite this