^(131)I-nor-β-CIT的制备及其大鼠体内分布

Synthesis, Labelling With ^(131)I and Distributionin Rats of nor-β-CIT

合成了 2β-甲酯基 - 3β- (4’-碘苯基 )去甲基托烷 (nor-β- CIT)及标记前体 2β-甲酯基 - 3β- (4’- (三丁基锡 )苯基 )去甲基托烷。nor- β- CIT及中间体的 IR、MS、HNMR、旋光分析等鉴定数据与结构相符。由标记前体制备 13 1I- nor- β- CIT,标记率 (80～ 90 ) % ,萃取后放化纯度 >95%。大鼠体内分布表明 ,13 1I- nor- β- CIT能很快进脑 ,且清除较慢 (注药后 5min、30 min和 4 h时脑的放射性摄取比分别为 2 .30、2 .54和 1.2 2 % ID)。丘脑、中脑、海马和额叶表现出较高的放射性摄取 ,注药后约 1h达到最大值 (分别为 1.77、1.78、1.54和 2 .13% ID)。额叶的摄取大于颞叶和顶叶 (1h时的放射性摄取分别为 2 .13、1.92、1.87% ID) ,与 5-

carbomethoxy-3β-(4'-iodophenyl)nortropane(nor-β-CIT) and it's labelling precursor 2β-carbomethoxy-3β-(4'-tribuylstannylphenyl)nortropane are synthesized, the chemical structures of nor-β-CIT and it's intermediates are confirmed by IR, MS, HNMR and rotation. The Radiochemical purity of 131 I-nor-β-CIT is over 95% evaluated by HPLC and TLC. Biodistribution in rats indicate rapid uptake and slow clearance of 131 I-nor-β-CIT in brain (2.30, 2.54 and 1.22 %ID respectively at 5, 30 and 240 min after injection). It displays high radiouptake in thalamencephalon, midbrain, hippocampi and frontal lobe, the maximum values are 1.77, 1.78, 1.54 and 2.13 %ID respectively at about 1 hour after injection. The value of uptake in frontal lobe is greater than in temporal lobe and in parietal lobe(2.13, 1.92 and 1.87 %ID), which are consistent with the distribution of serotonin transporter in the brain.