Kawai K, Fujibayashi Y, Saji H, Yonekura Y, Konishi J, Kubodera A, Yokoyama A
Faculty of Pharmaceutical Sciences, Science University of Tokyo, Japan.
J Nucl Med. 1991 May;32(5):819-24.
We examined the brain accumulation of iodine-123-iodo-alpha-methyl-L-tyrosine (123I-L-AMT) in mice and rats. I-L-AMT showed high brain accumulation in mice, and in rats; rat brain uptake index exceeded that of 14C-L-tyrosine. The brain uptake index and the brain slice studies indicated the affinity of I-L-AMT for carrier-mediated and stereoselective active transport systems, respectively; both operating across the blood-brain barrier and cell membranes of the brain. The tissue homogenate analysis revealed that most of the accumulated radioactivity belonged to intact I-L-AMT, an indication of its stability. Thus, 123I-L-AMT appears to be a useful radiopharmaceutical for the selective measurement of cerebral amino acid transport.
我们研究了碘-123-碘-α-甲基-L-酪氨酸（123I-L-AMT）在小鼠和大鼠体内的脑摄取情况。I-L-AMT在小鼠和大鼠体内均显示出高脑摄取，大鼠脑摄取指数超过了14C-L-酪氨酸。脑摄取指数和脑切片研究分别表明I-L-AMT对载体介导的和立体选择性主动转运系统具有亲和力；这两种转运系统均通过血脑屏障和脑细胞膜发挥作用。组织匀浆分析显示，大部分累积的放射性属于完整的I-L-AMT，这表明其具有稳定性。因此，123I-L-AMT似乎是一种用于选择性测量脑氨基酸转运的有用放射性药物。
