Abstract
Background The high metabolic activity of the heart makes it particularly suited to the use of hyperpolarized (HP) 13C methods to non-invasively detect and characterize metabolic changes that occur during ischemia/reperfusion (I/R). Energy metabolism in ischemic rat hearts has been previously interrogated with HP 13C-labelled pyruvate ex vivo, and its hyperpolarized metabolites have been imaged in the ischemic pig heart in vivo. In both cases, a decrease in the conversion to labelled bicarbonate was observed vs. conversion to lactate, consistent with the expected decrease in pyruvate oxidation. Here, our aim was to establish this I/R model in rats and to correlate metabolic changes with the area at risk. Methods
Highlights
The high metabolic activity of the heart makes it suited to the use of hyperpolarized (HP) 13C methods to non-invasively detect and characterize metabolic changes that occur during ischemia/reperfusion (I/R)
Myocardial ischemia was effected by occlusion with a snare installed around the left coronary artery, in place for 15 min, followed by another HP infusion and spectral acquisition
The 13C-bicarbonate-to-[1-13C]lactate (Bic-to-Lac) ratio was 0.68 ± 0.03 SEM the level of baseline (n=3), compared to 1.11 ± 0.10 in control experiments (n=5) (p=0.02), reflecting the shift from oxidative metabolism to anaerobic metabolism. (Figure 1) To reduce the mortality rate, another set of experiments was performed with the occluding thread placed more distally on the coronary artery; this resulted in a similar decrease in the Bic-to-Lac ratio, 0.75 ± 0.07 compared to baseline (n=8) (p=0.01 vs. control)
Summary
The high metabolic activity of the heart makes it suited to the use of hyperpolarized (HP) 13C methods to non-invasively detect and characterize metabolic changes that occur during ischemia/reperfusion (I/R). Energy metabolism in ischemic rat hearts has been previously interrogated with HP 13C-labelled pyruvate ex vivo, and its hyperpolarized metabolites have been imaged in the ischemic pig heart in vivo. In both cases, a decrease in the conversion to labelled bicarbonate was observed vs conversion to lactate, consistent with the expected decrease in pyruvate oxidation. Our aim was to establish this I/R model in rats and to correlate metabolic changes with the area at risk
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
