Abstract
GdDOTP5- is a highly charged, bone-seeking paramagnetic complex that could potentially detect bone lesions by magnetic resonance imaging (MRI). To date, its pharmacokinetics, effects on organ relaxivity, and interaction with hydroxyapatite (HA) has not been described. Liver, kidney, and bone MRI images were obtained on male white rabbits after the administration of GdDOTP5- or a gold standard MRI contrast agent, GdDTPA2-. Parallel in vitro experiments quantified the effect of HA binding on GdDOTP5- -induced changes in relaxivity. The 2 compounds showed similar MRI enhancements in visceral tissues, but no enhancement of bone was evident with GdDOTP5- despite confirmation of bone and HA binding of the radioactive 153SmDOTP5- and 111InDOTP5- derivatives. In vitro experiments demonstrated that GdDOTP5--induced changes in relaxivity were silenced upon HA binding but could be recovered by acid elution of the complex. HA binding assays revealed that GdDOTP5- is essentially MR silent when bound to bone, likely because of the exclusion of all outer sphere water molecules from the surface of the complex. These data suggest a novel strategy for creating highly sensitive, switchable MRI contrast agents.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
