Weiner R E, Schreiber G J, Hoffer P B, Bushberg J T
J Nucl Med. 1985 Aug;26(8):908-16.
The influence of various low molecular weight compounds on the transfer of 67Ga from human lactoferrin (LF) to horse spleen ferritin (HoFE) has been examined in vitro. When LF67Ga complex was placed in competition with HoFE using a dialysis system the initial transfer rate (TR) of 67Ga to HoFE was slow and continuous. In the presence of 1 mM pyrophosphate (PPi) ascorbate and adenosine triphosphate (ATP), the TR was dramatically enhanced. This effect was concentration sensitive since reduction of the ATP to 0.1 mM eliminated the enhancement. Other intracellular compounds did not significantly influence the TR. Although PPi and ascorbate ions yielded larger TR's, ATP was more effective in the promotion of 67Ga transfer to HoFE. When the LF/HoFE concentration ratio was decreased, in the presence of ATP, the transfer of 67Ga was significantly increased. These results suggest that ferritin present intracellularly could remove and retain 67Ga entering the cell in the form of a LF67Ga complex. Moreover, increased synthesis of ferritin and cytosolic phosphate compounds would appear to enhance this process.
已在体外研究了各种低分子量化合物对67Ga从人乳铁蛋白（LF）向马脾铁蛋白（HoFE）转移的影响。当使用透析系统使LF67Ga复合物与HoFE竞争时，67Ga向HoFE的初始转移速率（TR）缓慢且持续。在存在1 mM焦磷酸（PPi）、抗坏血酸盐和三磷酸腺苷（ATP）的情况下，TR显著提高。这种效应具有浓度敏感性，因为将ATP浓度降至0.1 mM会消除这种增强作用。其他细胞内化合物对TR没有显著影响。尽管PPi和抗坏血酸离子产生的TR更大，但ATP在促进67Ga向HoFE转移方面更有效。当LF/HoFE浓度比降低时，在ATP存在的情况下，67Ga的转移显著增加。这些结果表明，细胞内存在的铁蛋白可以去除并保留以LF67Ga复合物形式进入细胞的67Ga。此外，铁蛋白和胞质磷酸盐化合物合成的增加似乎会增强这一过程。
