The synthesis of 11 beta-methoxy-[16 alpha-123I] iodoestradiol and its interaction with the estrogen receptor in vivo and in vitro.
In order to produce an estrogen receptor mediated imaging agent, we have synthesized 11 beta-methoxy-16 alpha-iodoestradiol labeled with 123I, and have studied its interaction with the estrogen receptor and its distribution in rats and rabbits. This 123I-labeled steroid, 11 beta-methoxy-16 alpha-[123I]iodoestradiol, binds with high affinity, Ka = 6 x 10(9) M-1, and specificity to the estrogen receptor in uterine cytosol. When tested in vivo, this radiolabeled steroid concentrates by a receptor mediated mechanism, in the estrogen target tissue, the uterus, producing very high target to nontarget tissue ratios. The results of these experiments indicate that 11 beta-methoxy-16 alpha-[123I]iodoestradiol may be a useful imaging agent for clinically monitoring and detecting estrogen receptor containing tumors.
Zielinski
J E
JE
Department of Obstetrics and Gynecology, Yale University School of Medicine, New Haven, Connecticut 06510.
Larner
J M
JM
Hoffer
P B
PB
Hochberg
R B
RB
D000818:Animals; D003600:Cytosol / Q000378:metabolism; D004958:Estradiol / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000378:metabolism / Q000493:pharmacokinetics; D005260:Female; D066298:In Vitro Techniques; D007457:Iodine Radioisotopes; D009376:Neoplasms, Hormone-Dependent / Q000000981:diagnostic imaging; D011817:Rabbits; D011877:Radionuclide Imaging; D051381:Rats; D011919:Rats, Inbred Strains; D011960:Receptors, Estrogen / Q000378:metabolism*; D014018:Tissue Distribution; D014599:Uterus / Q000378:metabolism
D007457:Iodine Radioisotopes; D011960:Receptors, Estrogen; C060160:11-methoxy-16-iodoestradiol; D004958:Estradiol