Urinary excretion of unconjugated and conjugated 3,5-diiodothyronine.
A radioimmunoassay for the estimation of 3,5-diiodothyronine (3,5-T2) in human urine has been established. The urinary excretion of both glucuronide and sulfate conjugates of 3,5-T2 were estimated after enzymatic deconjugation. In 19 healthy controls the median excretion of unconjugated 3,5-T2 was 276 pmol/d, whereas the median excretion of glucuronidated and sulfated 3,5-T2 in 7 healthy subjects was 448 and 451 pmol/d, respectively. The median excretion of 154 pmol/d in 9 hypothyroid patients did not differ from that found in controls. In contrast 12 patients with hyperthyroidism had an enhanced excretion, 1312 pmol/d (P less than 0.01). Compared with previous data on the daily degradation of 3,5-T2, it is concluded that approximately one-sixth of degradated 3,5-T2 is excreted in the urine.
D000328:Adult; D000368:Aged; D004104:Diiodothyronines / Q000652:urine*; D005260:Female; D005965:Glucuronates / Q000652:urine; D006042:Goiter / Q000652:urine; D006801:Humans; D006980:Hyperthyroidism / Q000652:urine; D007037:Hypothyroidism / Q000652:urine; D008297:Male; D008875:Middle Aged; D011863:Radioimmunoassay; D013431:Sulfates / Q000652:urine; D013970:Thyronines / Q000652:urine*
D004104:Diiodothyronines; D005965:Glucuronates; D013431:Sulfates; D013970:Thyronines; C030103:3,5-diiodothyronine