title: IV Administered Gadodiamide Enters the Lumen of the Prostatic Glands: X-Ray Fluorescence Microscopy Examination of a Mouse Model.
abstract: OBJECTIVE
  Dynamic contrast-enhanced MRI (DCE-MRI) has become a standard component of multiparametric protocols for MRI examination of the prostate, and its use is incorporated into current guidelines for prostate MRI examination. Analysis of DCE-MRI data for the prostate is usually based on the distribution of gadolinium-based agents, such as gadodiamide, into two well-mixed compartments, and it assumes that gadodiamide does not enter into the glandular lumen. However, this assumption has not been directly tested. The purpose of this study was to use x-ray fluorescence microscopy (XFM) imaging in situ to measure the concentration of gadodiamide in the epithelia and lumens of the prostate of healthy mice after IV injection of the contrast agent.
  
  
  METHODS
  Six C57Bl6 male mice (age, 28 weeks) were sacrificed 10 minutes after IV injection of gadodiamide (0.13 mmol/kg), and three mice were sacrificed after saline injection. Prostate tissue samples obtained from each mouse were harvested and frozen; 7-μm-thick slices were sectioned for XFM imaging, and adjacent 5-μm-thick slices were sectioned for H and E staining. Elemental concentrations were determined from XFM images.
  
  
  RESULTS
  A mean (± SD) baseline concentration of gadolinium of 0.01 ± 0.01 mM was determined from XFM measurements of prostatic tissue samples when no gadodiamide was administered, and it was used to determine the measurement error. When gadodiamide was added, the mean concentrations of gadolinium in the epithelia and lumens in 32 prostatic glands from six mice were 1.00 ± 0.13 and 0.36 ± 0.09 mM, respectively.
  
  
  CONCLUSIONS
  Our data suggest that IV administration of gadodiamide results in uptake of contrast agent by the glandular lumens of the mouse prostate. We were able to quantitatively determine gadodiamide distributions in mouse prostatic epithelia and lumens.
authors: 1 Department of Radiology, University of Chicago, 920 E 58th St (CLSC-109), Chicago, IL 60637.
authors: Devkumar
authors: D
authors: Mustafi
authors: 2 Advance Proton Source, Argonne National Laboratory, Lemont, IL.
authors: Sophie-Charlotte
authors: SC
authors: Gleber
authors: 2 Advance Proton Source, Argonne National Laboratory, Lemont, IL.
authors: Jesse
authors: J
authors: Ward
authors: 3 Department of Medicine, University of Chicago, Chicago, IL.
authors: Urszula
authors: U
authors: Dougherty
authors: 1 Department of Radiology, University of Chicago, 920 E 58th St (CLSC-109), Chicago, IL 60637.
authors: Marta
authors: M
authors: Zamora
authors: 1 Department of Radiology, University of Chicago, 920 E 58th St (CLSC-109), Chicago, IL 60637.
authors: Erica
authors: E
authors: Markiewicz
authors: 1 Department of Radiology, University of Chicago, 920 E 58th St (CLSC-109), Chicago, IL 60637.
authors: David C
authors: DC
authors: Binder
authors: 4 Department of Pathology, University of Chicago, Chicago, IL.
authors: Tatjana
authors: T
authors: Antic
authors: 2 Advance Proton Source, Argonne National Laboratory, Lemont, IL.
authors: Stefan
authors: S
authors: Vogt
authors: 1 Department of Radiology, University of Chicago, 920 E 58th St (CLSC-109), Chicago, IL 60637.
authors: Gregory S
authors: GS
authors: Karczmar
authors: 1 Department of Radiology, University of Chicago, 920 E 58th St (CLSC-109), Chicago, IL 60637.
authors: Aytekin
authors: A
authors: Oto
mesh_terms: D000818:Animals; D003287:Contrast Media / Q000008:administration & dosage / Q000493:pharmacokinetics*; D004848:Epithelium / Q000000981:diagnostic imaging / Q000378:metabolism; D019786:Gadolinium DTPA / Q000008:administration & dosage / Q000493:pharmacokinetics*; D007275:Injections, Intravenous; D008279:Magnetic Resonance Imaging; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008856:Microscopy, Fluorescence; D023421:Models, Animal; D011467:Prostate / Q000000981:diagnostic imaging* / Q000378:metabolism*; D011859:Radiography
chemical_list: D003287:Contrast Media; C064925:gadodiamide; D019786:Gadolinium DTPA
keywords: dynamic contrast-enhanced MRI; gadodiamide distribution in prostatic tissues; mouse prostate; prostatic lumen; x-ray fluorescence microscopy