Saini S K, Jena A, Dey J, Sharma A K, Singh R
Institute of Nuclear Medicine and Allied Sciences, Lucknow Marg, Delhi, India.
Magn Reson Imaging. 1995;13(7):985-90. doi: 10.1016/0730-725x(95)00046-j.
Manganese-tetrasulfonated phthalocyanine (MnPcS4) has been evaluated as a potential contrast agent in Magnetic resonance imaging (MRI) for tumor localisation in mice. MnPcS4 showed favourable molar relaxivity, much better than Gd-DTPA and comparable to tetrasulfonated manganese complex of porphyrin (TPPS4). Tumors showed selective retention of the metal complex (dye) with the peak value reached at 24 hours following intravenous administration. Dye concentration in tumors remained consistently higher than either kidney or muscle tissue both at 1 and 24 hours and a 10-fold increase in tumor-to-muscle ratio over the control was seen at 24 hr. Normal liver tissue, however, showed higher concentration than tumor at all times during the study. A linear correlation was found between longitudinal relaxation rate (1/T1) and the corresponding concentration of MnPcS4 in various tissues. MR imaging done in animals using 1.5 T superconducting clinical imager showed a mean percent increase in signal intensity of 131.8% (SD +/- 32.86) in the tumor and a 70% increase in tumor-to-muscle ratio over the pretreatment value, at 24 hr. The results suggest that MnPcS4 is a potential tumor-selective contrast agent in MRI.
四磺酸锰酞菁（MnPcS4）已被评估为磁共振成像（MRI）中用于小鼠肿瘤定位的潜在造影剂。MnPcS4显示出良好的摩尔弛豫率，比钆-二乙三胺五乙酸（Gd-DTPA）好得多，与卟啉的四磺酸锰配合物（TPPS4）相当。肿瘤显示出对金属配合物（染料）的选择性摄取，静脉给药后24小时达到峰值。在1小时和24小时时，肿瘤中的染料浓度始终高于肾脏或肌肉组织，并且在24小时时，肿瘤与肌肉的比值比对照组增加了10倍。然而，在研究期间，正常肝脏组织在所有时间的浓度都高于肿瘤。在各种组织中，纵向弛豫率（1/T1）与相应的MnPcS4浓度之间发现了线性相关性。使用1.5 T超导临床成像仪对动物进行的MR成像显示，在24小时时，肿瘤中的信号强度平均增加了131.8%（标准差±32.86），肿瘤与肌肉的比值比预处理值增加了70%。结果表明，MnPcS4是MRI中一种潜在的肿瘤选择性造影剂。
