3,5-T2 stimulates oxygen consumption, but not glucose uptake in human mononuclear blood cells.
L-thyroxine (T4), L-triiodothyronine (T3) and 3,5-di-iodothyronine (T2) rapidly (within 30 min) stimulated oxygen consumption in human mononuclear blood cells, whereas the D isomers of T4 and T3 and Triac had no stimulatory effect. Oxygen consumption was stimulated by the same magnitude by equimolar concentrations (5-500 nmol/l) of L-T4, L-T3 and 3,5-T2 reaching a plateau at 100 nmol/l of 0.025 umol/mg DNA x h. The stimulatory effects of T4 and T3, but not of T2 were inhibited by PTU. Glucose uptake was stimulated only by L-T4 and L-T3, whereas 3,5-T2, Triac and the D-isomers of T4 and T3 had no effect. The dose response curve reached an apparent maximum at 100 nmol/l of 0.30 mmol/l x mg DNA x h and PTU had no effect on iodothyronine stimulated glucose uptake. We conclude that 3,5-T2 is a significant intracellular stimulator of oxygen consumption, whereas T3 and T4 stimulate glucose uptake.
Kvetny
J
J
Department of Clinical Chemistry, Odense University, Denmark.
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism*; D004247:DNA / Q000096:biosynthesis; D004104:Diiodothyronines / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D008875:Middle Aged; D009504:Neutrophils / Q000187:drug effects / Q000378:metabolism*; D010101:Oxygen Consumption / Q000187:drug effects*; D013974:Thyroxine / Q000494:pharmacology; D014284:Triiodothyronine / Q000494:pharmacology
D001786:Blood Glucose; D004104:Diiodothyronines; D014284:Triiodothyronine; C030103:3,5-diiodothyronine; D004247:DNA; D013974:Thyroxine