Regional brain uptake and retention of Tc-99m-propylene amine oxime derivatives

Conference · Wed May 01 04:00:00 EDT 1985 · J. Nucl. Med.; (United States)

OSTI ID:6760920

Chaplin, S B; Oberle, P O; Hoffman, T J; Volkert, W A; Holmes, R A; Nowotnik, D P; Pickett, R D; Neirinckx, R

Tc-99m-propylene amine oxime (Tc-99m-PnAO) is a neutral lipophilic chelate that rapidly and passively enters the cerebral cortex (80% on first pass in baboon brain) and then clears exponentially leaving inadequate activity to perform conventional SPECT brain imaging. When side chains are attached to the PnAO backbone lipophilicity is increased, as well as brain retention. In this work the authors evaluated regional brain uptake and retention of Tc-99m-PnAO and several of its derivatives in rat brain using serial autoradiography (ARG). Autoradiographs of each Tc-99m chelate at 5 sec. post peak brain uptake demonstrate discrete grey to white matter differentiation. White matter tracts are well delineated and the darker areas of grey matter appearing in the midbrain and thalamus, corresponding to areas of high capillary density and high blood flow documented with C-14-iodoantipyrine, are easily distinguished. Within 5 min. of the peak uptake the regional uptake and grey/white differentiation is lost on the Tc-99m-PnAO ARG. In contrast the 5 min. ARG of the more lipophilic Tc-99m, chelate with dimethyl-PnAO (DMPnAO) shows the complete reverse of the 5 sec. ARG, with greater activity in the white matter tracts than in the grey matter. One of the derivatives, tetramethyl-PAO (TMPAO) complexed with Tc-99m is retained in the grey matter of rat brain and shows persistent grey to white localization for at least 60 min., analogous to what has been reported with I-123-IMP. These results suggest that Tc-99m-TMPAO or one of its derivatives may be appropriate for SPECT imaging of cerebral blood flow abnormalities.

• Research Organization: Univ. of Missouri, Columbia, MO
• OSTI ID: 6760920
• Report Number(s): CONF-850611-
• Conference Information: Journal Name: J. Nucl. Med.; (United States) Journal Volume: 26:5
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
AMINES
ANIMALS
AUTORADIOGRAPHY
BABOONS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOCHEMISTRY
BIOLOGICAL LOCALIZATION
BLOOD FLOW
BODY
BRAIN
CENTRAL NERVOUS SYSTEM
CEREBRAL CORTEX
CEREBRUM
CHELATES
CHEMISTRY
COMPLEXES
COMPUTERIZED TOMOGRAPHY
DIAGNOSTIC TECHNIQUES
DIAGNOSTIC USES
DISTRIBUTION
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
EMISSION COMPUTED TOMOGRAPHY
EVALUATION
FUNCTIONS
HOURS LIVING RADIOISOTOPES
HYDROXY COMPOUNDS
INTERMEDIATE MASS NUCLEI
IODINE 123
IODINE ISOTOPES
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
LABELLED COMPOUNDS
LABELLING
MAMMALS
MONKEYS
NERVOUS SYSTEM
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANS
OXIMES
PRIMATES
RADIOISOTOPES
RADIOPHARMACEUTICALS
RATS
RETENTION FUNCTIONS
RODENTS
SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY
TECHNETIUM 99
TECHNETIUM COMPLEXES
TECHNETIUM ISOTOPES
THALAMUS
TISSUE DISTRIBUTION
TOMOGRAPHY
TRANSITION ELEMENT COMPLEXES
UPTAKE
USES
VERTEBRATES
YEARS LIVING RADIOISOTOPES