Inhibition by rifamycin AF/013 of thyroid hormone binding to the nuclear receptor.
Rifamycin AF/013, a potent inhibitor of nucleic acid polymerizing enzymes and of some hormone receptors, strongly inhibited thyroid hormone-binding to the isolated nuclear receptor. Fifty percent inhibition was obtained at AF/013 concentration of as low as 8 micrograms/ml. AF/013, however, only weakly promoted dissociation of the bound hormone from the receptor. The inhibitory action of AF/013 was competitive with respect to and reduced the receptor's affinity for the hormone.
Inoue
A
A
Department of Biochemistry, Osaka City University Medical School.
Higashi
Y
Y
Yukioka
M
M
Morisawa
S
S
D000818:Animals; D001667:Binding, Competitive; D002467:Cell Nucleus / Q000378:metabolism*; D004247:DNA / Q000378:metabolism / Q000494:pharmacology; D007457:Iodine Radioisotopes; D007700:Kinetics; D008099:Liver / Q000648:ultrastructure*; D051381:Rats; D011919:Rats, Inbred Strains; D011988:Receptors, Thyroid Hormone / Q000187:drug effects / Q000378:metabolism*; D012294:Rifamycins / Q000494:pharmacology*; D014284:Triiodothyronine / Q000378:metabolism*
D007457:Iodine Radioisotopes; D011988:Receptors, Thyroid Hormone; D012294:Rifamycins; D014284:Triiodothyronine; C006019:AF 013; D004247:DNA