Relationship of the eye uptake of N-isopropyl-p-(/sup 123/I)iodoamphetamine to melanin production
Eye uptake has been a potential concern with N-isopropyl-p-(/sup 123/I)iodoamphetamine (I-123 IMP) because it has been observed in certain animal species. The authors have investigated the cause of the eye uptake and its relationship to melanin synthesis. In a 1-yr-old cynomolgus monkey, high concentration of the tracer was seen in the eyes regardless of the type of anesthesia (pentobarbital or ketamine) or the oral administration of Lugol's solution. The eye uptake at 24 hr after injection of I-123 IMP was equally high in an 8-yr-old rhesus monkey. The ratio of radioactivity in the eye of black compared with white albino mice was 10:1 at 30 min, 18:1 at 2 hr and 36:1 at 24 hr after injection if I-123 IMP. No eye uptake above soft-tissue background was seen in five patients at 2, 24, and 48 hr after injection. I-123 IMP is avidly incorporated into melanocytes actively producing melanin, but substantially less in melanocytes where production of melanin has ceased as in the human eye.
- Research Organization:
- Harvard Medical School, Boston, MA
- OSTI ID:
- 5029211
- Journal Information:
- J. Nucl. Med.; (United States), Vol. 25:3
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AMINES
UPTAKE
EYES
RADIOISOTOPE SCANNING
RADIONUCLIDE KINETICS
IODINE 123
MELANIN
BIOSYNTHESIS
MONKEYS
SYMPATHOMIMETICS
ANIMALS
AUTONOMIC NERVOUS SYSTEM AGENTS
BETA DECAY RADIOISOTOPES
BODY
BODY AREAS
COUNTING TECHNIQUES
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
FACE
HEAD
HOURS LIVING RADIOISOTOPES
HYDROXY COMPOUNDS
INTERMEDIATE MASS NUCLEI
IODINE ISOTOPES
ISOTOPES
MAMMALS
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANS
PIGMENTS
PRIMATES
RADIOISOTOPES
SENSE ORGANS
SYNTHESIS
VERTEBRATES
550601* - Medicine- Unsealed Radionuclides in Diagnostics
560172 - Radiation Effects- Nuclide Kinetics & Toxicology- Animals- (-1987)