Magnesium orotate elicits acute cardioprotection at reperfusion in isolated and in vivo rat hearts.

Orotic acid and its salts chronically administered have been shown to significantly improve cardiac function in pathological settings associated with ischemia-reperfusion (I/R) injury. The aim of our study was to investigate the effect of magnesium orotate (Mg-Or) administration at the onset of post-ischemic reperfusion on myocardial function and infarct size (IS). Ex-vivo experiments performed on isolated perfused rat hearts were used to compare Mg-Or administration with a control group (buffer treated), ischemic post-conditioning, orotic acid treatment, and MgCl2 treatment.

High-resolution respirometry with multiple substrates titration in permeabilized myocardial fibers.

The present study was purported to standardize the high-resolution respirometry technique for the analysis of oxidative phosphorylation (OXPHOS) in saponin-skinned cardiac fibers. Preparation of permeabilized myocardial fibers allows the assessment of respiratory function of the entire population of mitochondria in their normal intracellular position. Adult male rat ventricular bundles were permeabilized with saponin (50 microg/ml) and samples (1-3 mg wet weight) were transferred into the Oxygraph-2k (OROBOROS Instr.