A Novel Method for Mitochondrial Membrane Potential Detection in Heart Tissue Following Ischemia-reperfusion in Mice.

OBJECTIVE

Myocardial ischemia-reperfusion (I/R) injury is associated with a significant reduction in the mitochondrial membrane potential (MMP, ΔΨm). Fluorescence-based assays are effective for labelling active mitochondria in living cells; their application in heart tissue, however, represents a challenge because of a low yield of viable cardiomyocytes after cardiac perfusion. This study aimed to examine a novel method for detecting the changes in the MMP of mouse heart tissue following I/R injury.

METHODS

The I/R model was established, which was characterized by distinct ischemic area and apoptosis in heart tissue. The MMP was detected via a confocal microscope after the ascending aorta was clamped and the mitochondrial probe solution (containing Mito-Tracker Deep Red FM) was perfused from the apex via a peristaltic pump.

RESULTS

This method enabled the distribution of the probe solution throughout the cardiac tissue via the coronary circulation. Fluorescence detection revealed that the MMP was profoundly reduced in both ischemic area and border area following I/R when compared with that in the sham group. There was no obvious difference in the MMP of the remote area between the I/R group and the sham group.

CONCLUSION

This study presents a novel method for detecting the MMP in heart tissue, and this method will facilitate the evaluation of changes in the MMP in different regions following I/R.