Propylthiouracil-d5 is intended for use as an internal standard for the quantification of propylthiouracil by GC- or LC-MS. Propylthiouracil (PTU) is a thioamide antithyroid agent.1 It inhibits thyroid peroxidase activity in rat and monkey thyroid microsomes (IC50s = 0.081 and 4.1 μM, respectively). PTU (30 mg/kg) increases thyroid weight and serum thyroid stimulating hormone levels and decreases serum 3,5,3'-triiodothyronine and thyroxine levels in rats. Sensitivity to the bitter taste of PTU is genetically mediated and is associated with increased sensitivity to other sweet and bitter compounds.2 Formulations containing propylthiouracil have been used in the treatment of Graves' disease and hyperthyroidism.
1.Takayama, S., Aihara, K., Onodera, T., et al.Antithyroid effects of propylthiourad and sulfamonomethoxine in rats and monkeysToxicol. Appl. Pharmacol.82(2)191-199(1986) 2.Drewnowski, A., and Rock, C.L.The influence of genetic taste markers on food acceptanceAm. J. Clin. Nutr.62(3)506-511(1995)