Lauffer R B, Parmelee D J, Dunham S U, Ouellet H S, Dolan R P, Witte S, McMurry T J, Walovitch R C
EPIX Medical, Cambridge, MA 02142-1118, USA.
Radiology. 1998 May;207(2):529-38. doi: 10.1148/radiology.207.2.9577506.
To evaluate the protein-binding and signal enhancement characteristics of MS-325, a gadolinium-based magnetic resonance (MR) imaging blood pool agent that binds to albumin, and compare results with those obtained with existing gadolinium- and iron oxide-based agents.
Protein binding in human plasma was measured by means of ultrafiltration. T1 relaxation times (20 MHz) were measured in human plasma or ex vivo samples from rabbits and monkeys injected with 0.1 mmol of MS-325 per kilogram of body weight. Imaging (three-dimensional fast imaging with steady-state precession, or FISP) was performed at 1.0 T in phantoms, which contained varying concentrations of different agents, or rabbits after injection of 0.015-0.100 mmol/kg MS-325.
MS-325 is 80%-96% bound in human plasma and exhibits a relaxivity approximately six to 10 times that of gadolinium diethylenetriaminepentaacetic acid (DTPA). Images of phantoms containing MS-325 were significantly brighter than those containing existing gadolinium chelates or iron particles (monocrystalline iron oxide nanoparticle, or MION) at equivalent concentrations. Findings of in vivo studies indicated strong, persistent plasma T1 reduction with MS-325 for 1 hour (T1 of MS-325, 50-100 msec; T1 of Gd-DTPA, 200-400 msec) and strong vascular enhancement on MR images.
MS-325 is highly protein bound after injection and provides vascular signal enhancement superior to that provided with other agents. As the first gadolinium-based blood pool agent in human trials, MS-325 has the potential to enhance both dynamic and steady-state MR angiograms.
评估MS - 325（一种与白蛋白结合的钆基磁共振成像血池造影剂）的蛋白结合和信号增强特性，并将结果与现有的钆基和氧化铁基造影剂所得结果进行比较。
通过超滤法测量人血浆中的蛋白结合情况。在注射每千克体重0.1 mmol MS - 325的人血浆或兔和猴的离体样本中测量T1弛豫时间（20 MHz）。在1.0 T下对含有不同浓度不同造影剂的模型或注射0.015 - 0.100 mmol/kg MS - 325后的兔进行成像（三维稳态进动快速成像，即FISP）。
MS - 325在人血浆中的结合率为80% - 96%，其弛豫率约为钆二乙三胺五乙酸（DTPA）的6至10倍。在等效浓度下，含有MS - 325的模型图像比含有现有钆螯合物或铁颗粒（单晶氧化铁纳米颗粒，即MION）的图像明显更亮。体内研究结果表明，MS - 325可使血浆T1持续显著降低1小时（MS - 325的T1为50 - 100毫秒；钆 - DTPA的T1为200 - 400毫秒），并且在磁共振图像上有强烈的血管增强。
MS - 325注射后与蛋白高度结合，提供优于其他造影剂的血管信号增强。作为人类试验中的首个钆基血池造影剂，MS - 325有潜力增强动态和稳态磁共振血管造影。
