INVIVO SPECT IMAGING OF CNS D-2 DOPAMINE-RECEPTORS - INITIAL STUDIES WITH IODINE-123-IBZM IN HUMANS

  • 1 May 1990
    • journal article
    • research article
    • Vol. 31  (5) , 573-579
Abstract
Iodobenzamide (IBZM) is a D-2 dopamine receptor antagonist. In this paper the results of Phase I clinical studies of iodine-123-(123I) IBZM in humans are reported. Preliminary imaging studies, both planar and single-photon emission tomography (SPECT), of no-carrier added [123I]IBZM in humans show specific localization in the basal ganglia of the brain. At 2 hr after an i.v. injection, the brain uptake was 3.72% of the dose, and at 20 hr later the uptake diminished to 0.7%. Radiation dosimetry calculation indicated that the radiation dose to the brain was minimum, 0.039 rad/mCi, while the large intestine wall received the highest dose, 0.28 mrad/mCi. The radiation dosimetry and pharmacology data suggest that this agent is safe for human use.