Brown adipose tissue imaging using the TSPO tracer [18F]fluoromethyl-PBR28-d2: A comparison with [18F]FDG

摘要: Abstract Introduction Currently, the reference method of brown adipose tissue (BAT) imaging is 18F-fluorodeoxyglucose positron emission tomography ([18F]FDG PET). BAT by [18F]FDG PET requires additional stimulation process, which inconvenient and hard to be standardized. The translocator protein 18 kDa (TSPO) has been found effective for visualization BAT. Herein, we evaluated feasibility [18F]fluoromethyl-PBR28-d2 ([18F]fmPBR28-d2), a TSPO tracer, interscapular in comparison with PET. Methods C57BL/6 mice were used [18F]fmPBR28-d2 imaging. was performed thermoneutral condition (n = 5) after cold exposure (4 °C 4 h) on next day using same mice. conditions Ex vivo biodistribution study ten (5: thermoneutral, 5: exposure). immunohistochemistry done Results images showed prominent uptakes under both conditions. While, uptake significantly higher than (12.83 ± 5.06 vs. 22.50 ± 6.03, P = 0.007). Also, (8.40 ± 0.63 21.41 ± 4.03, P = 0.001). background (thigh muscle) ratio also (8.86 ± 1.74 vs.16.93 ± 4.74, P = 0.036). IHC demonstrated that expression increased group. Conclusions [18F]FmPBR28-d2 regardless stimulation, condition. Further works are warranted assess clinical significance