Shiba K, Mori H, Matsuda H, Hisada K
Radioisotope Center, School of Medicine, Kanazawa University, Japan.
Int J Rad Appl Instrum B. 1992 Apr;19(3):303-10. doi: 10.1016/0883-2897(92)90115-f.
A new ligand, an N-p-iodophenethyl diaminodithiol (DADT-IPE), an anlog of N-isopropyl-p-iodoamphetamine (IMP), was synthesized and subsequently complexed with 99mTc, using stannous chloride as a reducing agent. Two complexes (a and b) were separated from 99mTc-DADT-IPE by high performance liquid chromatography (HPLC). Competitive inhibition studies showed that the IC50 value of DADT-IPE (70 microM) was similar to that of IMP (49 microM). Biodistribution studies of one of the complexes [99mTc-DADT-IPE(a)] in rats showed that 0.65% of the injected dose of the tracer remained in the brain at 5 min after intravenous injection, with 0.53% of the dose remaining in the brain at 60 min post-injection, whereas the corresponding values for the other complex [99mTc-DADT-IPE(b)] were 0.34% dose in the brain at 5 min and 0.28% dose in the brain at 60 min post-injection. The half-life for clearance of 99mTc-DADT-IPE(a) from rat brain was found to be more than 5 h. These results suggested that 99mTc-DADT-IPE(a) has characteristics which are suitable for cerebral perfusion imaging.
一种新的配体，N-对碘苯乙基二氨基二硫醇（DADT-IPE），N-异丙基对碘安非他明（IMP）的类似物，被合成出来，随后使用氯化亚锡作为还原剂使其与99mTc络合。通过高效液相色谱法（HPLC）从99mTc-DADT-IPE中分离出两种络合物（a和b）。竞争性抑制研究表明，DADT-IPE的IC50值（70 microM）与IMP的IC50值（49 microM）相似。对其中一种络合物[99mTc-DADT-IPE(a)]在大鼠体内的生物分布研究表明，静脉注射后5分钟，示踪剂注射剂量的0.65%留在脑中，注射后60分钟，该剂量的0.53%留在脑中，而另一种络合物[99mTc-DADT-IPE(b)]的相应值在注射后5分钟为脑中剂量的0.34%，在注射后60分钟为脑中剂量的0.28%。发现99mTc-DADT-IPE(a)从大鼠脑中清除的半衰期超过5小时。这些结果表明，99mTc-DADT-IPE(a)具有适合脑灌注显像的特性。
