Kinetics of 99mTc-labeled pyrophosphate and polyphosphate in man.
Kinetics of 99mTc-labeled pyrophosphate and polyphosphate in man.
复制标题
99mTc 标记的焦磷酸盐和多磷酸盐在人体中的动力学。
作者：
G. T. Krishnamurthy;R. Huebotter;C. Walsh;J. Taylor;M. Kehr;M. Tubis;W. Blahd
在一项联合研究中，对 10 名患者的 99mTc 标记的焦磷酸盐的动力学与多磷酸盐的动力学进行了比较。两种药物均以双指数方式从血液中清除。两者的指数 I 的半场清除时间相同，并且比指数 ii 的半场清除时间短。两种药物在第一小时内的尿排泄量相同，但在接下来的 3 小时内，Tc-焦磷酸盐的清除速度稍快一些，从而导致血液背景放射性较低。两种药物均与血浆蛋白松散结合，主要是与球蛋白部分结合。两者的病变检测灵敏度相似。使用两种试剂均获得了出色的骨图像。由于血液背景较低，Tc-焦磷酸盐的图像始终表现出色，并且从相同区域积累相同数量的计数所需的时间更短。在使用99mTc复合物的量时，没有发现低钙血症或手足抽搐，对无机磷和碱性磷酸酶的1小时血清水平也没有任何显着影响。注射后4小时，9.5%的Tc-焦磷酸盐在血液中循环，31.7%通过尿液排出，其余58.8%被骨和其他组织吸收。 Tc-聚磷酸盐的相应值在血液中为12.5%，在尿液中为29.0%，在骨和其他组织中为58.5%。在软组织中，泌尿生殖系统的可视化最为一致。结论是，Tc-焦磷酸盐和Tc-聚磷酸盐都是优良的骨骼显像剂，并且Tc-焦磷酸盐似乎略优于Tc-聚磷酸盐。
Thekinetic of 99mTc-labeled pyrophosphate were compared with those of polyphosphate in ten patients in a combined study. Both agents cleared from the blood in a biexpoential fashion. The clearance half-time of Exponent I was the same for both and was shorter than the clearance half-time of Exponent ii. Urinary excretion of both agents was the same during the first hour but during the next 3 hr Tc-pyrophosphate cleared at a slightly more rapid rate, resulting in lower blood background radioactivity. Both agents were bound loosely to plasma proteins, mainly to globulin fractions. The sensitivity of lesion detection was similar for both. Excellent bone images were obtained with both agents. The images with Tc-pyrophosphatewere consistently superior owing to the low blood background and they took less time to accumulate an identical number of counts from identical regions. With the amount of 99mTc-complex used, no hyocalcemia or tetany was noted, nor was there any significant effect on 1-hr serum levels of inorganic phosphours and alkaline phosphatase. Four hours after injection, 9.5% of the dose of Tc-pyrophosphate was circulating in blood, 31.7% was excreted in urine, and the remaining 58.8% was taken up by bone and other tissues. The corresponding values with Tc-polyphosphate were 12.5% in blood, 29.0% in urine, and 58.5% in bone and other tissues. Among the soft tissues, the genitourinary system is most consistently visualized. It is concluded that both Tc-pyroposphate and Tc-polyphosphate are excellent skeletal-imaging agents and that Tc-pyrophosphate appears slightly superior to Tc-polyphosphate.