Inflammatory
cytokines have been shown to have many cardiotoxic effects and to be activated in patients who have had a
myocardial infarction (MI).
Angiotensin-converting enzyme (
ACE) inhibitors have been shown to have multiple beneficial effects after MI, but until now, their effects on cardiac
cytokine expression were unknown. It was hypothesized that
ACE inhibitors reduce cardiac
cytokine expression and that this is associated with improved cardiac remodeling and hemodynamics. Rats had an MI created by coronary artery
ligation and
ACE inhibitors were started either early (day 1) or late (day 25) after MI and followed for a total of 28 days after MI. In the early-post-MI group,
quinapril improved cardiac hemodynamics, improved
ventricular remodeling, and prevented the increase in the expression of several cardiac
cytokines (interleukin-1beta and -6) and reduced the cardiac expression of other
cytokines (
tumor necrosis factor-alpha and
interleukin-5). The late introduction of
quinapril (for 3 days) resulted in similar beneficial hemodynamic effects, and reductions in cardiac
cytokines but did not result in improved cardiac remodeling. Thus, following MI,
ACE inhibitors reduce cardiac
cytokine expression both chronically and subacutely, an effect that may contribute to their beneficial effects after MI.