Vagenakis A G, Portnay G I, O'Brian J T, Rudolph M, Arky R A, Ingbar S H, Braverman L E
J Clin Endocrinol Metab. 1977 Dec;45(6):1305-9. doi: 10.1210/jcem-45-6-1305.
The metabolic clearance and production rates of thyroxine (T4) and triiodothyronine (T3) were measured in 9 obese euthyroid patients prior to and during prolonged starvation. The metabolic clearance rates (MCR) and serum concentrations of T4, and, therefore, the metabolic degradation or production rates of T4 were unchanged during starvation. Serum T3 concentrations decreased strikingly during starvation, from 145 +/- 7 ng/dl (mean +/- SE) to 66 +/- 9 ng/dl (P < 0.001), while the mean MCR of T3 was unchanged, with the result that T3 degradation or production rates were markedly decreased (36.4 +/- 4.5 μg/d vs. 11.2 +/- 0.7 μg/d; P < 0.001). These findings suggest that the decrease in serum T3 concentration observed during starvation results from a decrease in the peripheral conversion of T4 to T3.
在9名肥胖的甲状腺功能正常患者长期饥饿之前及期间，测量了甲状腺素（T4）和三碘甲状腺原氨酸（T3）的代谢清除率及生成率。饥饿期间，T4的代谢清除率（MCR）和血清浓度，以及T4的代谢降解或生成率均未改变。饥饿期间血清T3浓度显著下降，从145±7 ng/dl（均值±标准误）降至66±9 ng/dl（P<0.001），而T3的平均MCR未变，结果是T3降解或生成率显著降低（36.4±4.5 μg/d对11.2±0.7 μg/d；P<0.001）。这些发现提示，饥饿期间观察到的血清T3浓度降低是由于T4向T3的外周转化率降低所致。
