[11C]FTIMD was prepared by a palladium-promoted cross-coupling reaction of the tributylstannyl precursor and [11C]methyl iodide in the presence of tris(dibenzylideneacetone)dipalladium(0) and tri(o-tol)phosphine. Biodistribution was investigated in rats by tissue dissection. [11C]FTIMD metabolites were measured in brain tissues and plasma. Dynamic PET scans were acquired in rats, and the kinetic parameters estimated.
[11C]FTIMD was successfully synthesized with a suitable radioactivity for the injection. Co-injection with 0.1 mg/kg of cold FTIMD and BU224 induced a significant reduction in the brain-to-blood ratio 15 and 30 min after the injection. In metabolite analysis, unchanged [11C]FTIMD in the brain was high (98 % ) 30 min after the injection. In PET studies, high radioactivity levels were observed in regions with a high density of I2R. The radioactivity levels and VT values in the brain regions were prominently reduced by 1.0 mg/kg of BU224 pretreatment as compared with control.
[11C]FTIMD showed specific binding to I2Rs in rat brains with a high density of I2R.