摘要本文通过^131I标记延胡索乙素(THP)以探讨其在小鼠体内的分布代谢。采用氯胺-T法对THP进行^131I标记;以三氯甲烷萃取,聚酰胺薄膜为介质、正己烷:三氯甲烷:甲醇:醋酸=2:3:0.5:0.055(V/V)为展开剂,测定标记物的标记率和放化纯;KM小鼠尾静脉注射^131I-延胡索乙素(185kBq/只,n=6),分别于注射后5、10、30、60、120、240、1440min取各脏器、及脑部额叶、顶叶、枕叶、海马、纹状体、丘脑和血,称重、计数,计算每克组织百分注射剂量率(%ID·g^-1)。结果表明,^131I-延胡索乙素标记率达76%,纯化后其放化纯为97.3%,7和20天后分别为95.4%、96.8%;动物实验显示^131I-延胡索乙素在小鼠体内广泛分布,主要经肝和。野进行代谢,5min时%ID·g^-1分别为14.35、6.55,脂肪和肠也有较高分布,5min时ID·g^-1分别为3.05、3.91;脑组织中5~10min即达峰值,各脑区均有分布,其中以顶叶、额叶和小脑略高,2h后脑中基本代谢完毕。由此可见,碘标延胡索乙素标记物稳定,体内主要经肝。野代谢,脂肪及脑内各区域也有较高分布,可用于进一步的微量示踪研究。
The work was to investigate radioiodinated tetrahydropalmatine and its biodistribution in mice. Tetrahydropalmatine was labeled with ^131I using the chloramine-T method and the labeled compound were characterized by polyamide TLC. The animals were sacrificed at different times after radiopharmaceutical i.v. administration. The interested tissues samples were collected, and percent injected dose per gram (%ID·g^-1) was calculated for each sample. The labeling yield of ^131I-tetrahydropalmatine was 76% and its RCPs were 97.3%, 95.4%, and 96.8% after 1, 7 and 20 days, respectively. Biodistribution in mice demonstrated that ^131I-tetrahydropalmatine was extensive, and it was metabolized mainly in liver and kidney, which contained of 14.35% and 6.55% ID·g^-1at 5main, respectively, with 3.26% and 1.20% ID·g^-1at 4h, respectively. Comparatively high ^131I-tetrahydropalmatine was found in intestine and fat, but clearance was slow, 3.91%and 3.05% at 5 min and decreased to 0.79% and 0.37% at 4 h. The results also showed that ^131I-tetmhydropalmatine could well penetrate the blood-brain barrier to attain a maximal level in brain tissue within 5~10 min, but it mostly was cleaned out after 2 h. There was no significant difference in brain regions despite of highest biodistribution in parietal lobe. In conclusion, ^131I-tetrahydropalmatine was stable and it was metabolized mainly in liver and kidney, but there was no significant difference in brain regions.