Frondoza C G, Trivedi S M, Humphrey R L, Goble J C
J Nucl Med. 1980 Jan;21(1):52-8.
[6-14C]arginine, injected intraperitoneally into normal rats, was cleared from the plasma with biphasic decay kinetics. Urinary excretion was efficient (32% of the 25-muCi dose within the first 24 hr) with no preferential tissue retention. In mice, the effective duration of the radiotracer's availability for protein biosynthesis was less than 30 min. When the tracer was administered i.v. to patients with multiple myeloma, it was similarly cleared from the plasma with biphasic kinetics, and was excreted rapidly in the urine (22% of the dose within the first 24 hr). In patients, the guanido-tagged arginine labeled only tumor M component, and the labeling was most intense in patients who had far advanced disease. Estimated radiation dose to humans from a 100-muCi injection was 10 mrads. These studies demonstrate the fesibility of in vivo labeling with [16 -14C]arginine, with minimal radiation hazard, thus providing a simple, sensitive, and specific method for monitoring the synthesis of the plasmacytoma M component in patients with multiple myeloma.
将[6-14C]精氨酸腹腔注射到正常大鼠体内后，其从血浆中清除呈现双相衰减动力学。尿排泄效率较高（在最初24小时内，25微居里剂量的32%经尿液排出），且无组织选择性潴留。在小鼠中，放射性示踪剂用于蛋白质生物合成的有效持续时间不到30分钟。当将该示踪剂静脉注射给多发性骨髓瘤患者时，其同样以双相动力学从血浆中清除，并迅速经尿液排出（在最初24小时内，剂量的22%经尿液排出）。在患者中，胍基标记的精氨酸仅标记肿瘤M成分，且在病情晚期患者中标记最为强烈。一次100微居里注射对人体估计的辐射剂量为10毫拉德。这些研究证明了用[16-14C]精氨酸进行体内标记的可行性，辐射危害极小，从而为监测多发性骨髓瘤患者浆细胞瘤M成分的合成提供了一种简单、灵敏且特异的方法。
