Janssen K P, Van Der Heide D, Visser T J, Kaptein E, Beynen A C
Department of Human and Animal Physiology, Agricultural University, Wageningen, The Netherlands.
Biol Trace Elem Res. 1994 Mar;40(3):237-46. doi: 10.1007/BF02950796.
The hypothesis tested was whether marginal iodine deficiency for a period of 6 wk affects iodothyronine deiodinase activities in liver and brain of rats. Male rats were fed purified diets either deficient or sufficient in iodine; the diets were fed on a restricted basis (60% of ad libitum intake). Body weight gain of the two groups was comparable. Iodine deficiency was evidenced by increased thyroid weight (26%), reduced urinary iodine excretion (80%), and reduced plasma T4 concentrations (22%). Activities of liver type I and brain type III deiodinase were unchanged, but the activity of type II deiodinase in brain was increased (28%) in the iodine-deficient rats. Food restriction per se significantly lowered T3 (30%) and T4 (22%) concentrations in plasma and decreased type III deiodinase activity in brain (30%). These results indicate that in marginal iodine deficiency the activities of hepatic type I deiodinase and brain type III deiodinase are unchanged, whereas that of brain type II deiodinase is increased.
所检验的假设是，为期6周的边缘性碘缺乏是否会影响大鼠肝脏和大脑中的碘甲状腺原氨酸脱碘酶活性。给雄性大鼠喂食碘缺乏或充足的纯化日粮；日粮按限制量喂食（自由摄入量的60%）。两组大鼠的体重增加情况相当。甲状腺重量增加（26%）、尿碘排泄减少（80%）以及血浆T4浓度降低（22%）证明存在碘缺乏。肝脏I型和大脑III型脱碘酶的活性未发生变化，但缺碘大鼠大脑中II型脱碘酶的活性增加了（28%）。食物限制本身显著降低了血浆中的T3（30%）和T4（22%）浓度，并降低了大脑中III型脱碘酶的活性（30%）。这些结果表明，在边缘性碘缺乏状态下，肝脏I型脱碘酶和大脑III型脱碘酶的活性未发生变化，而大脑II型脱碘酶的活性增加。
