title: Retinoic acid decreases retinoic acid and triiodothyronine nuclear receptor expression in the liver of hyperthyroidic rats.
abstract: Retinoic acid (RA) and triiodothyronine (T3) exert many of their actions by binding to specific nuclear receptors (respectively, RA receptor (RAR) and T3) receptor (TR) belonging to a 'superfamily' of receptors. Some heterologous regulation of these receptors has been shown, and in particular regulation of the maximum binding capacity of TR by either retinol or RA. Now, using hyperthyroidic rats as a model, the effect of RA on binding capacity and on the mRNA levels of TR and RAR was investigated. The results show that the benefit of vitamin A treatment for the hyperthyroidic state, which has been described for a long time, could be the result of a down-heteroregulation of TR by RA, the active metabolite of retinol.
authors.affiliation: Laboratoire de Nutrition, ISTAB, Université Bordeaux I, Talence, France.
authors.forename: P
authors.initials: P
authors.lastname: Higueret
authors.forename: V
authors.initials: V
authors.lastname: Pallet
authors.forename: M
authors.initials: M
authors.lastname: Coustaut
authors.forename: I
authors.initials: I
authors.lastname: Audouin
authors.forename: J
authors.initials: J
authors.lastname: Begueret
authors.forename: H
authors.initials: H
authors.lastname: Garcin
mesh_terms: D000818:Animals; D001345:Autoradiography; D001483:Base Sequence; D002352:Carrier Proteins / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D002850:Chromatography, Gel; D004247:DNA; D006980:Hyperthyroidism / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D018168:Receptors, Retinoic Acid; D011988:Receptors, Thyroid Hormone / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D014212:Tretinoin / Q000494:pharmacology*
chemical_list: D002352:Carrier Proteins; D012333:RNA, Messenger; D018168:Receptors, Retinoic Acid; D011988:Receptors, Thyroid Hormone; D014212:Tretinoin; D004247:DNA