OAT3-mediated extrusion of the 99mTc-ECD metabolite in the mouse brain

J Cereb Blood Flow Metab. 2014 Apr;34(4):585-8. doi: 10.1038/jcbfm.2014.20. Epub 2014 Feb 5.


After administration of the (99m)Tc complex with N,N'-1,2-ethylenediylbis-L-cysteine diethyl ester ((99m)Tc-ECD), a brain perfusion imaging agent, the radioactive metabolite is trapped in primate brain, but not in mouse and rat. Here, we investigate the involvement of metabolite extrusion by organic anion transporter 3 (OAT3), which is highly expressed at the blood-brain barrier in mice, in this species difference. The efflux rate of radioactivity in the cerebrum of Oat3(-/-) mice at later phase was 20% of that of control mice. Thus, organic anion transporters in mouse brain would be involved in the low brain retention of radioactivity after (99m)Tc-ECD administration.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blood-Brain Barrier / diagnostic imaging
  • Blood-Brain Barrier / metabolism*
  • Cerebrum / diagnostic imaging
  • Cerebrum / metabolism*
  • Cysteine / analogs & derivatives*
  • Cysteine / metabolism
  • Cysteine / pharmacokinetics
  • Injections, Intravenous
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Organic Anion Transporters, Sodium-Independent / genetics
  • Organic Anion Transporters, Sodium-Independent / physiology*
  • Organotechnetium Compounds / metabolism*
  • Organotechnetium Compounds / pharmacokinetics
  • Radiopharmaceuticals / metabolism*
  • Radiopharmaceuticals / pharmacokinetics
  • Tomography, Emission-Computed, Single-Photon


  • Organic Anion Transporters, Sodium-Independent
  • Organotechnetium Compounds
  • Radiopharmaceuticals
  • organic anion transport protein 3
  • technetium Tc 99m bicisate
  • Cysteine