title: Synthesis and evaluation of 7 alpha-iodo-5 alpha-dihydrotestosterone as a potential radioligand for androgen receptor.
abstract: 7 alpha-Iodo-17 beta-hydroxy-5 alpha-androstan-3-one (7 alpha-iodo-5 alpha-dihydrotestosterone, 7 alpha-IDHT) has been synthesized as a potential radioligand for the detection and measurement of androgen receptor and for imaging of androgen-receptor-containing tissues when labeled with the gamma-emitting radionuclides 125I and 123I, respectively. In vitro binding studies show that 7 alpha-IDHT binds with high affinity to the rat and human androgen receptor (RBA = 74) compared to R1881 (RBA = 100). Further, this compound showed high specificity for the androgen receptor. 7 alpha-IDHT showed only a marginal affinity for the progestin receptor and even less affinity for the estrogen receptor. No binding was detected to the glucocorticoid receptor. These characteristics make 7 alpha-IDHT a potentially ideal agent for imaging and evaluation of androgen-receptor-containing tissues.
authors.affiliation: Department of Chemistry, State University of New York, Old Westbury 11568.
authors.forename: R M
authors.initials: RM
authors.lastname: Hoyte
authors.forename: K
authors.initials: K
authors.lastname: Borderon
authors.forename: K
authors.initials: K
authors.lastname: Bryson
authors.forename: R
authors.initials: R
authors.lastname: Allen
authors.forename: R B
authors.initials: RB
authors.lastname: Hochberg
authors.forename: T J
authors.initials: TJ
authors.lastname: Brown
mesh_terms: D000818:Animals; D001667:Binding, Competitive; D013196:Dihydrotestosterone / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000378:metabolism; D006801:Humans; D007457:Iodine Radioisotopes; D015741:Metribolone / Q000378:metabolism; D015394:Molecular Structure; D011397:Promegestone / Q000378:metabolism; D051381:Rats; D011944:Receptors, Androgen / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism; D011965:Receptors, Glucocorticoid / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism
chemical_list: C086913:7-iodo-17-hydroxy-3-androstanone; D007457:Iodine Radioisotopes; D011944:Receptors, Androgen; D011960:Receptors, Estrogen; D011965:Receptors, Glucocorticoid; D011980:Receptors, Progesterone; D013196:Dihydrotestosterone; D015741:Metribolone; D011397:Promegestone