Dillman E, Gale C, Green W, Johnson D G, Mackler B, Finch C
Am J Physiol. 1980 Nov;239(5):R377-81. doi: 10.1152/ajpregu.1980.239.5.R377.
Iron-deficient rats become hypothermic and have an excessive catecholamine response when exposed to an ambient temperature of 4 degrees C. This is not due to changes in body insulation, since thickness is unaltered, since differences persist after removal of hair, and since cutaneous vasoconstriction is intact. On the other hand, oxygen consumption of iron-deficient animals at 4 degrees C is reduced, 39 +/- 3 ml . kg-1 . min-1 compared to 63 +/- 2 in control animals. Thyroxine (T4) values at 4 degrees C were 4.34 +/- 0.20 microgram/dl sera as compared to control values of 3.6 +/- 0.32. Triiodothyronine (T3) values of iron-deficient animals in the cold were 48 +/- 6.8 ng/dl as compared to 72 +/- 5.6 in control animals. Treatment of iron-deficient animals with iron was shown to normalize the plasma T3 response at 4 degrees C within 6 days. Thyroidectomized iron-deficient animals injected with T3 did not show hypothermia at 4 degrees C, whereas thyroidectomized iron-deficient animals injected with T4 showed hypothermia, increased catecholamines, and decreased T3 levels as compared to non-iron-deficient animals similarly treated. It is proposed that iron deficiency impairs conversion of T4 to T3 and that this is primarily responsible for the hypothermia observed.
缺铁大鼠在暴露于4摄氏度的环境温度下会出现体温过低的情况，并且儿茶酚胺反应过度。这并非由于身体隔热的变化，因为毛发厚度未改变，去除毛发后差异仍然存在，并且皮肤血管收缩功能完好。另一方面，缺铁动物在4摄氏度时的耗氧量降低，为39±3毫升·千克⁻¹·分钟⁻¹，而对照动物为63±2。4摄氏度时甲状腺素（T4）值为4.34±0.20微克/分升血清，而对照值为3.6±0.32。缺铁动物在寒冷环境中的三碘甲状腺原氨酸（T3）值为48±6.8纳克/分升，而对照动物为72±5.6。给缺铁动物补铁后，6天内血浆T3反应在4摄氏度时恢复正常。甲状腺切除的缺铁动物注射T3后在4摄氏度时未出现体温过低，而甲状腺切除的缺铁动物注射T4后与同样处理的非缺铁动物相比出现体温过低、儿茶酚胺增加和T3水平降低。有人提出缺铁会损害T4向T3的转化，这主要是观察到的体温过低的原因。
