Morphine preconditioning, cardioprotection and left ventricular remodelling in rabbits

Area of Science:

• Cardiology
• Pharmacology
• Experimental Medicine

Background:

• Cardiac remodeling is a significant complication following myocardial infarction.
• Morphine is known for its analgesic properties and has been explored for potential cardioprotective effects.

Purpose of the Study:

• To investigate the cardioprotective effects of morphine preconditioning against cardiac remodeling in a rabbit model of myocardial ischemia-reperfusion (I/R) injury.

Main Methods:

• Male New Zealand rabbits underwent myocardial I/R injury.
• Rabbits were randomized into four groups: saline sham, morphine sham, saline control, and morphine preconditioning.
• Cardiac function and biological markers were assessed over 28 days using echocardiography and blood tests.

Main Results:

• Morphine preconditioning significantly improved hemodynamic parameters and reduced myocardial infarct size and troponin I levels one day post-I/R injury.
• At 28 days, B-type natriuretic peptide levels were lower, and left ventricular weight was increased in the morphine preconditioning group.
• Echocardiography revealed higher left ventricular ejection fraction and fractional shortening in the morphine preconditioning group compared to controls.

Conclusions:

• A single dose of morphine preconditioning provides a prolonged cardioprotective effect against cardiac remodeling after I/R injury.
• Morphine preconditioning enhances cardiac function and may reduce adverse post-infarction remodeling.