This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Davison, G. Articles by Wickline, S. A. Search for Related Content PubMed PubMed Citation Articles by Davison, G. Articles by Wickline, S. A.

Circulation, Vol 90, 1334-1342, Copyright © 1994 by American Heart Association

ARTICLES

Cellular mechanisms of captopril-induced matrix remodeling in Syrian hamster cardiomyopathy

G Davison, CS Hall, JG Miller, M Scott and SA Wickline
Department of Physics, Washington University School of Medicine, St Louis, MO 63110.

BACKGROUND: Although angiotensin-converting enzyme (ACE) inhibitors have become a mainstay of treatment for chronic congestive heart failure (CHF), it is not known whether the cardiac remodeling effects are a secondary phenomenon, resulting from ACE inhibitors' hemodynamic actions of afterload reduction, or occur through an independent mechanism. METHODS AND RESULTS: We used ultrasonic tissue characterization to define potentially salutary effects of treatment with ACE inhibitors on the material properties of the heart and its potential influence on cardiac remodeling at the cellular level. Ten 1- month-old, cardiomyopathic (CM) Syrian hamsters and 6 normal (NL) hamsters were treated with captopril (2 g/L water ad libitum), and 10 CM hamsters and 10 NL hamsters were maintained untreated for 3 months. Hearts were excised, and backscattered radiofrequency data were acquired from 1200 independent sites from each specimen with a high- resolution 50-MHz acoustic microscope for calculation of integrated backscatter (IB). Treatment with captopril reduced left ventricular mass, calcium concentration, and IB in CM hearts without affecting myofiber size or collagen concentration. The IB from grossly normal regions of myocardium in NL hamsters, treated CM hamsters, and untreated CM hamsters was not significantly different. The IB from the microscopic regions of scar tissue in treated CM hamsters was significantly less (P = .0004) than that from scar tissue in untreated CM hamsters. CONCLUSIONS: The reduced IB from treated scar tissue components reflects specific alterations in the material properties (elastic stiffness, density) of fibrous regions in CM hearts induced by captopril. This is the first report that defines specific cellular effects of ACE inhibitors on the material properties of isolated components of cardiac tissue in experimental cardiomyopathy. These alterations in material properties of scar tissue components represent a potential mechanism for the salutary actions of ACE inhibitors in heart failure.

This article has been cited by other articles:

				I. M.C. Dixon, J. Hao, N. L. Reid, and J. C. Roth Effect of chronic AT1 receptor blockade on cardiac Smad overexpression in hereditary cardiomyopathic hamsters Cardiovasc Res, May 1, 2000; 46(2): 286 - 297. [Abstract] [Full Text] [PDF]

				N. R. Bastien, A.-V. Juneau, J. Ouellette, and C. Lambert Chronic AT1 receptor blockade and angiotensin-converting enzyme (ACE) inhibition in (CHF 146) cardiomyopathic hamsters: effects on cardiac hypertrophy and survival Cardiovasc Res, July 1, 1999; 43(1): 77 - 85. [Abstract] [Full Text] [PDF]

				M. P. Reyes, R. Khatib, G. Khatib, K.L. Ho, F. Smith, and R. A. Kloner Prolonged Captopril Therapy in Murine Viral Myocarditis Journal of Cardiovascular Pharmacology and Therapeutics, January 1, 1998; 3(1): 43 - 49. [Abstract] [PDF]

				E. B. Williams, I. Halpert, S. Wickline, G. Davison, W. C. Parks, and J. N. Rottman Osteopontin Expression Is Increased in the Heritable Cardiomyopathy of Syrian Hamsters Circulation, August 15, 1995; 92(4): 705 - 709. [Abstract] [Full Text]