We investigated metabolic factors related to the recovery of myocardial function during
ischemia and after reperfusion using
dichloroacetic acid (DCA) in canine models with repeated 10-min regional
ischemia and reperfusion. Administration of 100 mg/kg DCA, which activates
pyruvate dehydrogenase, improved regional wall motion significantly as compared with the nontreated controls (p < 0.05). The mechanism was studied by determining changes in myocardial levels of pH,
glucose,
lactate, and
nonesterified fatty acids (
NEFA).
Glucose extraction was increased significantly during
ischemia and reperfusion by the pretreatment of DCA (p < 0.01). the calculated contribution of
glucose to myocardial oxidative metabolism during
ischemia and reperfusion was greater than that of
NEFA and
lactate in case of DCA treatment. The uptake of [
99mTc]pyrophosphate (PYP), which reflects myocardial injury, was also significantly suppressed by DCA (p < 0.01). pH was not affected by an infusion of DCA. These findings suggest that the activation of
glucose metabolism by DCA, which is impaired and reduced during
ischemia and reperfusion, may be responsible for the improved myocardial function after reperfusion.