Mak I T, Shrago E, Elson C E
Arch Biochem Biophys. 1983 Oct 1;226(1):317-23. doi: 10.1016/0003-9861(83)90298-9.
The role of adenine nucleotide translocase (AdNT) in the reduced oxidative metabolism of hypothyroidism has been examined. Both AdNT and respiratory activities in liver mitochondria of thyroidectomized rats were 30% below normal. Mitochondrial AdNT activities were determined by the back-exchange method of Pfaff and Klingenberg (Eur. J. Biochem. 6, 66, 1968). The Km and Vmax of the enzyme were temperature dependent. At physiological temperature, the Km and Vmax of the normal rat AdNT were 10 microM (for external ADP) and 4.73% s-1 (percentage efflux of the labeled adenine nucleotides), respectively. AdNT in hypothyroid rat liver mitochondria exhibited a 25-35% lower Vmax and 75% higher Km when assayed over the temperature range 0 to 37 degrees C. Dixonplot studies indicated that the AdNT in hypothyroidism was two- to threefold more sensitive to atractylate and palmitoyl-CoA inhibitions. In contrast the ADP-ATP translocase in hypothyroidism was more resistant than the control carrier to bongkrekate inhibition. The decrease in the transport of ADP, which is consistent with the decreased oxidative activity associated with hypothyroidism, apparently occurs secondary to changes in the lipid matrix of the inner mitochondrial membrane (F. L. Hoch (1977) Arch. Biochem. Biophys. 178, 535.).
已经研究了腺嘌呤核苷酸转位酶（AdNT）在甲状腺功能减退症氧化代谢降低中的作用。甲状腺切除大鼠肝脏线粒体中的AdNT和呼吸活性均比正常水平低30%。线粒体AdNT活性通过Pfaff和Klingenberg的反向交换法测定（《欧洲生物化学杂志》6卷，66页，1968年）。该酶的Km和Vmax与温度有关。在生理温度下，正常大鼠AdNT的Km和Vmax分别为10微摩尔（针对外部ADP）和4.73% s-1（标记腺嘌呤核苷酸的流出百分比）。当在0至37摄氏度的温度范围内测定时，甲状腺功能减退大鼠肝脏线粒体中的AdNT表现出Vmax低25 - 35%，Km高75%。Dixon图研究表明，甲状腺功能减退症中的AdNT对苍术苷和棕榈酰辅酶A抑制的敏感性高两到三倍。相比之下，甲状腺功能减退症中的ADP - ATP转位酶比对照载体对邦克雷酸抑制更具抗性。ADP转运的减少与甲状腺功能减退症相关的氧化活性降低一致，显然是线粒体内膜脂质基质变化的继发结果（F. L. Hoch（1977年）《生物化学与生物物理学报》178卷，535页）。
