Author + information
- Received May 21, 1986
- Revision received August 27, 1986
- Accepted September 12, 1986
- Published online April 1, 1987.
- Steven W. Werns, MD, FACC†,1,
- Michael J. Shea, MD‡,1,
- Ara Vaporciyan, BS1,
- Sem Phan, PhD, MD1,
- Gerald D. Abrams, MD1,
- Andrew J. Buda, MD, FACC1,
- Bertram Pitt, MD, FACC1 and
- Benedict R. Lucchesi, PhD, MD*
- ↵*Address for reprints: Benedict R. Lucchesi, PhD, MD, Department of Pharmacology, M6322 Medical Science Building I, The University of Michigan Medical School, Ann Arbor, Michigan 48109-0010.
Previous studies demonstrated that treatment with superoxide dismutase, a scavenger of superoxide anions, limits the extent of myocardial injury in a canine preparation of regional myocardial ischemia and reperfusion. Little is known, however, about the effects of superoxide dismutase on the healing of a myocardial infarct. Therefore, this study was performed to determine whether treatment with superoxide dismutase during myocardial ischemia impairs formation of scar tissue after infarction. Dogs received 2 hour infusions of superoxide dismutase or albumin (controls) by way of the left atrium beginning 15 minutes before and ending 15 minutes after a 90 minute occlusion of the left circumflex coronary artery. Six weeks later the animals were killed.
Two-dimensional echocardiography was performed before surgery and before induced death. Wall thickening in the central ischemic zone was decreased at 6 weeks compared with baseline studies (p < 0.05), but the decrease was similar for both groups. The hydroxyproline concentrations (μg/mg dry weight) of the scar tissue in the superoxide dismutase and control groups, respectively, were 35.3 ± 3.8 and 28.7 ± 5.0 (p < 0.05). The ratios of the scar thickness to normal wall thickness were superoxide dismutase 0.91 ± 0.03 and control 0.89 ± 0.03 (p > 0.05). Thus, superoxide dismutase had no adverse effect on wall thickening or scar formation assessed 6 weeks after myocardial infarction, and may be useful to limit oxygen radical-mediated damage during reperfusion of the ischemic myocardium.
with the technical assistance of Anthony Ventura
- Received May 21, 1986.
- Revision received August 27, 1986.
- Accepted September 12, 1986.
- American College of Cardiology Foundation