Pharmacologic effects of cannabidiol on acute reperfused myocardial infarction in rabbits: evaluated with 3.0T cardiac magnetic resonance imaging and histopathology.

Cannabidiol (CBD) has anti-inflammatory effects. We explored its therapeutic effects on cardiac ischemia-reperfusion injury with an experimental imaging platform. Reperfused acute myocardial infarction (AMI) was induced in rabbits with a 90-min coronary artery occlusion followed by 24-h reperfusion. Before reperfusion, rabbits received two intravenous doses of 100 μg/kg CBD (n=10) or vehicle (control, n=10). Evans blue was intravenously injected for later detection of the AMI-core. Cardiac magnetic resonance imaging (cMRI) was performed to evaluate cardiac morphology and function. After euthanasia, blood Troponin I (cTnI) was assessed, and the heart was excised and infused with multifunctional red-iodized-oil dye. The heart was sliced for digital radiography to quantify the perfusion density rate (PDR), area at risk (AAR), and myocardial salvage index (MSI), followed by histomorphologic staining. Compared to controls, CBD treatment improved systolic wall thickening (p<0.05), significantly increased blood flow in the AAR (p<0.05), significantly decreased microvascular obstruction (p<0.05), increased the PDR by 1.7-fold, lowered the AMI-core/AAR ratio (p<0.05), and increased the MSI (p<0.05). These improvements were associated with reductions in serum cTnI, cardiac leukocyte infiltration, and myocellular apoptosis (p<0.05). Thus, CBD therapy reduced AMI size and facilitated restoration of LV function. We demonstrated that this experimental platform has potential theragnostic utility.