Interaction of the antioestrogen ICI 164,384 with the oestrogen receptor.
The use of partially purified preparations of the human uterine oestrogen receptor has enabled, for the first time, a study of the binding of the steroidal, pure antioestrogen ICI 164,384 [N-n-butyl-11-(3,17 beta-dihydroxy-oestra-1,3,5(10)-trien-7 alpha-yl)N-methyl-undecamide] to the oestrogen receptor. Scatchard analyses of the binding of [3H]oestradiol and [3H]ICI 164,384 to the receptor show that the equilibrium dissociation constants for the interactions of these ligands with the receptor at 0 degrees C are 0.44 and 0.69 nM respectively. The concentration of receptor binding sites for the agonist was 1986 fmol/mg protein whilst that for the antagonist was 1400 fmol/mg protein. The affinity of the antioestrogen-receptor complex for DNA-cellulose does not increase following exposure to conditions that transform the oestrogen-receptor complex.
Weatherill
P J
PJ
Tenovus Institute for Cancer Research, University of Wales College of Medicine, Heath Park, Cardiff.
Wilson
A P
AP
Nicholson
R I
RI
Davies
P
P
Wakeling
A E
AE
D004958:Estradiol / Q000031:analogs & derivatives* / Q000378:metabolism; D004965:Estrogen Antagonists / Q000378:metabolism*; D005260:Female; D006801:Humans; D007700:Kinetics; D053284:Polyunsaturated Alkamides; D011960:Receptors, Estrogen / Q000378:metabolism*; D014599:Uterus / Q000378:metabolism*
D004965:Estrogen Antagonists; D053284:Polyunsaturated Alkamides; D011960:Receptors, Estrogen; D004958:Estradiol; C051781:ICI 164384