Technetium-99m HM-PAO stereoisomers: differences in interaction with glutathione

Journal Article · Thu Dec 01 04:00:00 EST 1988 · J. Nucl. Med.; (United States)

OSTI ID:6786154

Ballinger, J R; Reid, R H; Gulenchyn, K Y

(/sup 99m/Tc)HM-PAO exists as two stereoisomers, d,1 and meso, only one of which is retained in the brain. It has been suggested recently that the biodistribution of (99mTc)d,1-HM-PAO can be explained by its interaction with glutathione (GSH) in the tissues. We studied the interactions of the d,1 and meso isomers with GSH in vitro by measuring the partitioning of activity between ethyl acetate and aqueous GSH solutions at various concentrations. Partitioning of both isomers demonstrated a sigmoidal relationship with GSH concentration, but the d,1 isomer showed eightfold greater reactivity than the meso isomer. In a separate experiment, the d,1 isomer showed a sevenfold greater interaction rate with GSH than the meso isomer. These results suggest that the stereoisomers of (/sup 99m/TC)HM-PAO show differences in their interaction rate with GSH which may explain their different retention in the brain.

• Research Organization: Ottawa Civic Hospital, Ontario (Canada)
• OSTI ID: 6786154
• Journal Information: J. Nucl. Med.; (United States), Journal Name: J. Nucl. Med.; (United States) Vol. 29:12; ISSN JNMEA
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
AMINES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
BODY
BRAIN
CENTRAL NERVOUS SYSTEM
DISTRIBUTION
DRUGS
GLUTATHIONE
HOURS LIVING RADIOISOTOPES
HYDROXY COMPOUNDS
IN VITRO
INTERMEDIATE MASS NUCLEI
ISOMERIC NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOMERS
ISOTOPES
KINETICS
LABELLED COMPOUNDS
NERVOUS SYSTEM
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANOMETALLIC COMPOUNDS
ORGANS
OXIMES
PEPTIDES
POLYPEPTIDES
PROTEINS
RADIOISOTOPES
RADIOPHARMACEUTICALS
RADIOPROTECTIVE SUBSTANCES
REACTION KINETICS
RETENTION
TECHNETIUM 99
TECHNETIUM ISOTOPES
TISSUE DISTRIBUTION
YEARS LIVING RADIOISOTOPES