Quantitative Measurements for Type 1 Deiodinase Messenger Ribonucleic Acid in Human Peripheral Blood Mononuclear Cells: Mechanism of the Preferential Increase of T3 in Hyperthyroid Graves' Disease

Abstract To evaluate the regulatory mechanism of human Type 1 iodothyronine deiodinase (D1) gene expression, we measured the D1 mRNA levels in peripheral blood mononuclear cells (PBMC) in normal control subjects and in patients with Graves' disease. We used competitive reverse transcriptase-polymerase chain reaction with the deleted complimentary RNA of D1 as the standard for quantification. The D1 mRNA levels in PBMC were increased significantly in patients with Graves' disease compared with that in normal controls. There was a significant (p in vivo, and we postulate that a vicious spiral of increasing T3 and D1 is responsible for the exacerbation of thyrotoxicosis in hyperthyroid Graves' disease.