title: Regression of cardiac hypertrophy in cyp1a1ren-2 transgenic rats.
abstract: OBJECTIVE
  To evaluate the usefulness of the cyp1a1ren-2 transgenic rat model of inducible hypertension for studies of the development and regression of cardiac hypertrophy.
  
  
  METHODS
  Cyp1a1ren-2 rats received a diet containing 0% or 0.167% indole-3-carbinonl (I3C) for 4 weeks to induce hypertension. Cardiac magnetic resonance imaging (MRI) at 7 T was performed every second week for 10 weeks to measure left ventricular mass and the ejection fraction. Concomitantly, in six cyp1a1ren-2 rats blood pressure was recorded telemetrically.
  
  
  RESULTS
  Plasma prorenin concentrations rose from 138 ± 38 to 15,490 ± 3990 ng/angiotensin I/mL/h (P < 0.001) in I3C-treated transgenic rats and returned to basal levels after cessation of I3C. Mean blood pressure increased to a plateau of 169 ± 11 mmHg by the second week of induction. After cessation of I3C (day 28), arterial pressure dropped to values slightly below those prior to induction within 4 days (basal: 106 ± 7 mmHg, day 32: 103 ± 21 mmHg; NS). At day 28, left ventricular mass was increased by 39% vs. 4% in controls (P < 0.001) without changes of the ejection fraction. Cardiac hypertrophy was completely reversed at day 70, as evaluated by MRI.
  
  
  CONCLUSIONS
  The cyp1a1ren-2 transgenic rat is a useful model to study reversal and healing in the absence of surgical interventions.
authors.affiliation: Department of Cardiovascular Medicine, Institute of Physiology, University of Greifswald, Karlsburg, Germany. bspeters@gmx.de
authors.forename: Barbara S
authors.initials: BS
authors.lastname: Peters
authors.forename: Rami
authors.initials: R
authors.lastname: Dornaika
authors.forename: Norbert
authors.initials: N
authors.lastname: Hosten
authors.forename: Stefan
authors.initials: S
authors.lastname: Hadlich
authors.forename: John J
authors.initials: JJ
authors.lastname: Mullins
authors.forename: Jörg
authors.initials: J
authors.lastname: Peters
authors.forename: Rainer
authors.initials: R
authors.lastname: Rettig
mesh_terms: D000818:Animals; D019363:Cytochrome P-450 CYP1A1 / Q000235:genetics*; D004195:Disease Models, Animal; D006801:Humans; D006973:Hypertension / Q000150:complications* / Q000175:diagnosis*; D017379:Hypertrophy, Left Ventricular / Q000175:diagnosis* / Q000209:etiology*; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D051381:Rats; D055647:Rats, Transgenic; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D019363:Cytochrome P-450 CYP1A1