Kubota K, Kubota R, Yamada S, Tada M
Department of Nuclear Medicine, Tohoku University, Sendai, Japan.
Nucl Med Biol. 1995 Feb;22(2):193-8. doi: 10.1016/0969-8051(94)00099-6.
In order to examine in vivo effects of irradiation on tumor uptake of L-[methyl-11C]methionine at a cellular level, the distribution of L-[methyl-14C]methionine (Met) in a rat AH109A tumor model was investigated using microautoradiography. Silver grain density of tumor cell layer decreased rapidly within the first day after 20 Gy of irradiation, and continued to fall during day 2. Grain density of granulation tissue was 25% of tumor cells and was unchanged after irradiation. Macrophages and necrotic tissue showed low grain density and a small post-irradiation decrease. One day after irradiation, tumor cell showed giant cell formation and decreased cell density per unit area. The number of grains was greater in giant tumor cells than in non-irradiated tumor cell. Rapid response of Met uptake by tumor cells without a significant uptake by granulation tissue and macrophages suggest that 11C-Met is a suitable tracer for monitoring tumor radiotherapy with positron emission tomography.
为了在细胞水平上研究辐射对肿瘤摄取L-[甲基-¹¹C]蛋氨酸的体内效应，使用显微放射自显影术研究了L-[甲基-¹⁴C]蛋氨酸（Met）在大鼠AH109A肿瘤模型中的分布。20 Gy照射后的第一天内，肿瘤细胞层的银粒密度迅速下降，并在第2天持续下降。肉芽组织的银粒密度为肿瘤细胞的25%，照射后无变化。巨噬细胞和坏死组织的银粒密度较低，照射后下降幅度较小。照射后一天，肿瘤细胞出现巨细胞形成，单位面积的细胞密度降低。巨肿瘤细胞中的银粒数量多于未照射的肿瘤细胞。肿瘤细胞对Met摄取的快速反应以及肉芽组织和巨噬细胞无明显摄取，表明¹¹C-Met是用于正电子发射断层扫描监测肿瘤放疗的合适示踪剂。
