Using amitriptyline in the present study, overall uptake levels of [18F]TRACK in KM12 tumor tissue and in BAT could be significantly increased by 21 and 23% indicating that ligand activation of TrkA and TrkB in both tissues resulted in increased binding of [18F]TRACK at the intracellular kinase binding site as well. This evidence concerns the gene NTRK2 and neoplasm.