RESUMO
Cardiovascular diseases remains leading cause of death and disabilities. Coronary artery occlusion and consequent ischemia leads to acute myocardial infarction, but restoration of blood flow, paradoxically, provokes further myocardial damage known as reperfusion injury. Minocycline is possessing anti-inflammatory and anti-apoptotic activity, immune-modulating and antioxidative properties besides its primary antibacterial effect. Recently it gained significant interest in preventing cardiac damage especially due to myocardial ischemia/reperfusion injury (MI/RI). The aim of this study was to assess the protective ability of pre-treatment and post-treatment of isolated hearts from healthy and spontaneously hypertensive rats with minocycline, on functional recovery and redox status after MI/RI using Langendorff technique. Using sensor in the left ventricle, the cardiodynamic parameters were recorded and in the samples of the coronary venous effluent oxidative stress biomarkers were analyzed. Minocycline was injected directly into the coronary vessels, in pre-treatment 5 min before global ischemia, and in post-treatment during the first 5 min of reperfusion. Changes in redox balance induced by minocycline were more prominent in post-treatment fashion of application. Cardioprotective effects of minocycline due to MI/RI are even more significant in hypertensive hearts. Minocycline showed significant cardioprotective effects, which was more pronounced in hypertensive compared to healthy hearts. Reduction of pro-oxidative biomarkers was more prominent in hypertensive hearts compared to the normotensive, especially if it is applied in the form of post-treatment. Minocycline could be important tool in reduction of heart damage induced by MI/RI due to its antioxidative potential, if these results are confirmed by clinical study.