Abstract
1096
Objectives Previously we have demonstrated that burn injury increases uptake of FDG by the heart. In this investigation, we extended these studies to examine the effect of burn injury on cardiac uptake of CardioPET (trans-9-[18F]fluoro-3,4-methyleneheptadecanoic acid), a 18F labeled fatty acid, BFPET (4-[18F]fluorophenyltriphenylphosphonium), a marker of blood flow and FDG.
Methods The dorsums of male CD-1 mice (28-30 grams, n = 8) were subjected to a 30% full thickness scald burn (9 seconds, 90°C) followed by saline resuscitation (2 ml/kg). Shams control animals received the same treatment but without the burn. Each animal was fasted for 24 h followed by injection with 50 µCi of CardioPET, BFPET of FDG. Sixty-min, after tracer injection the animals were sacrificed and biodistribution of FDG, CardioPET or BFPET was determined. The organs of interest were excised and radioactivity was measured with a well-type gamma counter. All results were expressed as percent injected dose per gram (%ID/g, mean ± sem).
Results The results of these studies are summarized in the table. Clearly FDG and BFPET uptake by the myocardium were significantly (p<0.01)increased in burn injured vs. sham treated mice. However, cardiac uptake of CardioPET was not affected by the injury.
Conclusions Burn injury to mice increases BFPET uptake suggesting increased blood flow. However, myocardial uptake of CardioPET in burned mice was not significantly different from sham-treated controls, and might actually be less when the flow component is considered. The increased cardiac uptake of FDG following burn injury to mice may be related, in part, to the stress response which reduces the uptake of fatty acid, the preferred fuel for the heart.
Research Support Shriners Hospitals for Childre