The potential role of intracerebral glutathione in the retention of a representative 99MTc SNS/S mixed ligand complex in mice brain

The synthesis, radiochemistry and biodistribution in mice of 99mTcO{[(CH3CH2)2NCH2CH2-N(CH2CH2S)2] (p-SPh-COOCH2CH3)}, I, are reported herein. Complex I forms by binding of (CH3CH2)2NCH2CH2N(CH2CH2SH)2 and p-HSPhCOOCH2CH3 ligands to reduced 99mTc using glucoheptonate (GH) as transfer ligand. Corroboration of structure with an authentic 99gTc sample is achieved by reverse phase high pressure liquid chromatography (RP-HPLC) adopting parallel radiometric and photometric detection modes. By incubation at 37°C with glutathione (GSH) in aqueous medium I tranforms to an hydrophilic compound, as shown by HPLC. Tissue distribution experiments reveal high uptake and retention of I in mice brain.