Eplerenone attenuates cardiac dysfunction and oxidative stress in β-receptor stimulated myocardial infarcted rats

Navya M Reddy1, Umesh B Mahajan1, Chandragouda R Patil1

  • 1Cardiovascular Pharmacology Division, Department of Pharmacology, R. C. Patel Institute of Pharmaceutical Education and Research Shirpur-Dist-Dhule, Maharashtra, India.

Insights

Eplerenone treatment protected against isoproterenol-induced myocardial infarction in rats. It improved heart function and reduced cardiac damage by restoring hemodynamic, biochemical, and histopathological changes.

Area of Science:

  • Cardiology
  • Pharmacology

Background:

  • Myocardial infarction (MI) involves significant cardiac damage.
  • Isoproterenol is used to induce cardiotoxicity in experimental models.
  • Eplerenone is an aldosterone receptor antagonist with PI3K-Akt activity.

Purpose of the Study:

  • To investigate the protective effects of eplerenone against isoproterenol-induced myocardial infarction in rats.
  • To evaluate eplerenone's impact on hemodynamic, biochemical, and histopathological parameters post-MI.

Main Methods:

  • Rats were treated with isoproterenol to induce cardiotoxicity.
  • Oral pre-treatment with eplerenone (50, 100, 150 mg/kg) was administered daily for 14 days.
  • Hemodynamic, biochemical markers (cardiac enzymes, oxidative stress markers), and histopathological changes were assessed.

Main Results:

  • Isoproterenol induced significant cardiotoxicity, evidenced by ECG changes, altered pressures, and reduced cardiac function.
  • Eplerenone treatment dose-dependently restored hemodynamic parameters and cardiac enzyme activities.
  • Eplerenone significantly reduced oxidative stress markers (malondialdehyde) and increased antioxidant levels (glutathione, catalase, SOD), confirmed by histopathology.

Conclusions:

  • Eplerenone exhibits significant protective effects against experimental myocardial infarction.
  • The cardioprotective mechanism involves restoring hemodynamic function and mitigating oxidative stress.
  • Higher doses of eplerenone (100 and 150 mg/kg) demonstrated more pronounced protective effects.

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