Study On Metabolism And Imaging Of A New MRI Hepatobiliary Specific Contrast Agent Gd-DOTA-CSar-1

Objective(s):MRI hepatobiliary specific contrast agent has a prominent value in the diagnosis of hepatobiliary diseases.This study aims to synthesize a new contrast agent Gd-DOTA-CSar-1 based on cholylsarine,and explore its clinical application potential.Methods:1.The synthetic path of new MRI contrast agent Gd-DOTA-CSar-1 was explored and the target product was characterized by mass spectrometry.2.A new contrast agent Gd-DOTA-CSar-1 and Gd-EOB-DTPA solution with equal concentration gradient were prepared to measure and compare their relaxation rates in vitro.3.Gd ion content was detected after bile and urine drainage in rats,and the metabolism ratio of the new contrast agent Gd-DOTA-CSar-1 through liver and gallbladder and kidney was obtained.4.The distribution of the new contrast agent Gd-DOTA-CSar-1 in normal mice was obtained by MRI imaging,and the diagnostic value of Gd-DOTA-CSar-1MR imaging in mice with liver injury was evaluated.Results:1.In this study,a new type of contrast agent Gd-DOTA-CSar-1 was synthesized,and its molecular weight was consistent with that of theory(1006).2.In vitro relaxation rate experiment showed that the relaxation rate of the new contrast agent Gd-DOTA-CSar-1 was almost the same as that of Gd-EOB-DTPA(25.313/23.536).3.In rats,most of the new contrast agent Gd-DOTA-CSar-1 was metabolized by liver and biliary,and the liver/kidney excretion ratio was7.8/2.2.4.MRI imaging showed that the new contrast agent Gd-DOTA-CSar-1 was significantly enhanced in normal mice liver,gallbladder and kidney.In mice with liver injury,the liver showed rapid enhancement peak and then decreased to a stable level,gallbladder was not developed,and kidney enhancement was obvious.Conclusion(s):In this study,we synthesized a novel MRI contrast agent Gd-DOTA-CSar-lwith good relaxation rate,most of which are metabolized by the liver and the gallbladder,the imaging difference between normal mice and abnormal mice was obvious,showing good hepatobiliary specific contrast agent properties.