Lin Yung-Chang, Hung Guang-Uei, Luo Tsai-Yueh, Chen Chun-Hsiung, Hsia Chien-Chung, Hen Shu-Ling, Ho Yung-Jen, Lin Wan-Yu
Veterinary Medical Teaching Hospital, National Chung-Hsing University, Taiwan
J Vet Med Sci. 2006 Apr;68(4):367-71. doi: 10.1292/jvms.68.367.
111In-DTPA octreotide (DTPAOC) has been used for detecting somatostatin receptor positive tumor for years. In-111 DOTA-Tyr3-octreotide (DOTATOC) is newly developed for diagnostic and therapeutic purposes. In this study, we compared the biodistribution and tumor uptake ratio after injection of In-111 DTPAOC and In-111 DOTATOC in rats. Twelve rats bearing pancreatic tumors were divided into two groups: six rats were sacrificed at 4 hr after injection of 3.7 MBq of In-111 DTPAOC and another 6 rats were sacrificed at the same time after injection of 3.7 MBq of In-111 DOTATOC. Samples of various organs were obtained and counted to calculate the tissue concentration. In addition, 12 rats bearing pancreatic tumors were scanned at 4, 24, and 48 hr after injection of 37 MBq of In-111 DTPAOC or In-111 DOTATOC. The tumor uptake ratios (T/N ratio) were calculated. The biodistribution data showed that the activity in the tumor as well as in the kidney was significantly higher in the In-111 DOTATOC group than in the In-111 DTPAOC group, although both radiopharmaceuticals had the expected high affinity to the tumor. The T/N ratios in the In-111 DOTATOC group were also significantly higher than those in the In-111 DTPAOC group at 24 hr after injection. We conclude that In-111 DOTATOC showed lower clearance than In-111 DTPAOC in the rats bearing pancreatic tumors, although both of these radiopharmaceuticals showed expected high tumor uptake.
多年来，铟-111标记的二乙三胺五乙酸奥曲肽（DTPAOC）一直用于检测生长抑素受体阳性肿瘤。铟-111标记的DOTA-酪氨酰3-奥曲肽（DOTATOC）是新开发的用于诊断和治疗目的的药物。在本研究中，我们比较了大鼠注射铟-111 DTPAOC和铟-111 DOTATOC后的生物分布及肿瘤摄取率。12只患有胰腺肿瘤的大鼠被分为两组：6只大鼠在注射3.7MBq铟-111 DTPAOC后4小时处死，另外6只大鼠在注射3.7MBq铟-111 DOTATOC后于同一时间处死。获取各种器官样本并计数以计算组织浓度。此外，12只患有胰腺肿瘤的大鼠在注射37MBq铟-111 DTPAOC或铟-111 DOTATOC后的4、24和48小时进行扫描。计算肿瘤摄取率（T/N比值）。生物分布数据表明，尽管两种放射性药物对肿瘤都有预期的高亲和力，但铟-111 DOTATOC组肿瘤及肾脏中的活性明显高于铟-111 DTPAOC组。注射后24小时，铟-111 DOTATOC组的T/N比值也明显高于铟-111 DTPAOC组。我们得出结论，在患有胰腺肿瘤的大鼠中，铟-111 DOTATOC的清除率低于铟-111 DTPAOC，尽管这两种放射性药物都显示出预期的高肿瘤摄取。
