No inhibition by Li+ of thyroxine monodeiodination to 3,5,3'-triiodothyronine and 3,3',5'-triiodothyronine (reverse triiodothyronine).
The possibility that lithium affects the conversion of thyroxine to 3,5,3"-triiodothyronine and 3,3',5'-triiodothyronine (reverse triiodothyronine) was studied by measurement of the serum concentractions of these parameters in five patients during the first week of lithium therapy. In three patients there was a decrease in serum thyroxine concentration and a slightly less pronounced decrease in that of serum 3,5,3'-triiodothyronine. In two patients, who also received L-tryptophan or flupentixol, no change was noted in the concentrations of these compounds. There was no increase in serum 3,3',5'-triiodothyronine concentration in any of the patients. No systematic change was found in the serum concentrations of thyrotropin or unsaturated thyroid-hormone binding proteins. The results obtained do not support the contention that lithium should inhibit the monodeiodenation of thyroxine to its active and inactive metabolites.
D000328:Adult; D000342:Affective Symptoms / Q000188:drug therapy; D005260:Female; D006801:Humans; D008094:Lithium / Q000494:pharmacology* / Q000627:therapeutic use; D008875:Middle Aged; D011863:Radioimmunoassay; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood / Q000378:metabolism*; D013997:Time Factors; D014284:Triiodothyronine / Q000096:biosynthesis*
D014284:Triiodothyronine; D013972:Thyrotropin; D008094:Lithium; D013974:Thyroxine