Zanelli G D, Cook N, Lahiri A, Ellison D, Webbon P, Woolley G
Division of Radioisotopes, Clinical Research Centre, Harrow, Middlesex, UK.
J Nucl Med. 1988 Jan;29(1):62-7.
Most 99mTc/phosphine/isocyanide complexes synthesized to date show preferential uptake by the myocardium of many animal species but not in man. A new complex has been synthesized, [99mTc(DEPE)2(CNR)2], +(DEPIC), where R = t - butyl isocyanide, which in three animal species images the myocardium very well, but in humans it remains primarily in the blood pool. One reason for the difference in the behavior of these complexes in different species could be the characteristics of their binding to plasma proteins. The protein binding characteristics of DEPIC and two other well-known complexes have therefore been studied. Whereas the other complexes bind nonspecifically to many proteins both in animal and human plasma, DEPIC binds almost exclusively to prealbumin in humans but nonspecifically to other proteins in the rabbit. The binding sites in human plasma appear to be those normally occupied by thyroxine on the prealbumin tetramer and these can be blocked by sodium salicylate.
迄今为止合成的大多数99mTc/膦/异腈配合物在许多动物物种的心肌中显示出优先摄取，但在人体中则不然。一种新的配合物[99mTc(DEPE)2(CNR)2]+(DEPIC)已被合成，其中R =叔丁基异腈，它在三种动物物种中能很好地成像心肌，但在人体中它主要留在血池中。这些配合物在不同物种中行为差异的一个原因可能是它们与血浆蛋白结合的特性。因此，研究了DEPIC和其他两种著名配合物的蛋白结合特性。其他配合物在动物和人血浆中均非特异性地与多种蛋白结合，而DEPIC在人体中几乎只与前白蛋白结合，但在兔中则非特异性地与其他蛋白结合。人血浆中的结合位点似乎是甲状腺素在四聚体前白蛋白上通常占据的位点，这些位点可被水杨酸钠阻断。
