Schaap G H, Alferink T H, de Jong R B, Oe P L, Roos J C, Donker A J
Department of Internal Medicine, Free University Hospital, Amsterdam, The Netherlands.
Eur J Nucl Med. 1988;14(1):28-31. doi: 10.1007/BF00252614.
Animal studies have suggested that 99mTc-mercapto-acetylglycyl-glycyl-glycine (99mTc-MAG3) might be suitable for the determination of the renal plasma flow (RPF) because of its high renal clearance. In this study 131I-orthoiodohippurate (131I-OIH) and 99mTc-MAG3 (labeling always greater than 95%) were administered simultaneously in 11 patients (creatinine clearance ranging from 14 to 130 ml/min per 1.73 m2) to measure effective RPF(ERPF) using the standard technique (UV/P). Glomerular filtration rate (GFR; clearance of 125I-thalamate, 125I-OT) was also measured. The mean ratio of 99mTc-MAG3 clearance to 131I-IOH clearance was 0.55 +/- 0.02 (SEM), P less than 0.01, n = 16, and was independent of GFR and ERPF. To study this difference in renal handling of the radiopharmaceuticals, renal extractions by the right kidney were determined in another six patients after a single shot of the agents. Renal extraction of 99mTc-MAG3 was 0.60 +/- 0.03 after 5 min, and 0.41 +/- 0.08 after 30 min. Renal extraction of 131I-OIH amounted to 0.86 +/- 0.04 and 0.77 +/- 0.03, respectively. Using renal extractions of 0.41 and 0.77, respectively, it appeared that calculated renal plasma flows measured simultaneously with 99mTc-MAG3 and 131I-OIH were similar. Protein binding 30 min after the priming dose was 66% for 99mTc-MAG3 and 47% for 123I-OIH. We conclude that in spite of a high renal clearance (ratio to 125I-OT clearance 2.69 +/- 0.27), 99mTc-MAG3 seems unsuitable for an accurate determination of the RPF.(ABSTRACT TRUNCATED AT 250 WORDS)
动物研究表明，99m锝-巯基乙酰甘氨酰甘氨酰甘氨酸（99mTc-MAG3）因其高肾清除率可能适用于测定肾血浆流量（RPF）。在本研究中，对11例患者（肌酐清除率为每1.73平方米14至130毫升/分钟）同时给予131碘-邻碘马尿酸（131I-OIH）和99mTc-MAG3（标记率始终大于95%），采用标准技术（UV/P）测量有效肾血浆流量（ERPF）。还测量了肾小球滤过率（GFR；125碘-马尿酸盐、125I-OT的清除率）。99mTc-MAG3清除率与131I-IOH清除率的平均比值为0.55±0.02（标准误），P＜0.01，n = 16，且与GFR和ERPF无关。为研究放射性药物在肾脏处理上的这种差异，在另外6例患者单次注射药物后测定右肾的肾摄取量。99mTc-MAG3在5分钟后的肾摄取量为0.60±0.03，30分钟后为0.41±0.08。131I-OIH的肾摄取量分别为0.86±0.04和0.77±0.03。分别采用0.41和0.77的肾摄取量计算，似乎同时用99mTc-MAG3和131I-OIH测量的计算肾血浆流量相似。首剂给药30分钟后，99mTc-MAG3的蛋白结合率为66%，123I-OIH为47%。我们得出结论，尽管99mTc-MAG3肾清除率高（与125I-OT清除率的比值为2.69±0.27），但它似乎不适用于准确测定RPF。（摘要截短于250字）
