Osty J, Zhou Y, Chantoux F, Francon J, Blondeau J P
Unité de Recherche sur la Glande Thyroïde et la Régulation Hormonale U.96, Institut National de la Santé et de la Recherche Médicale, Kremlin-Bicêtre, France.
Biochim Biophys Acta. 1990 Jan 23;1051(1):46-51. doi: 10.1016/0167-4889(90)90172-a.
The kinetic properties of the carrier-mediated transport of 3,5,3'-triiodo-L-thyronine (T3) in washed rat erythrocytes were investigated (1) by studying the effects of trans unlabelled T3 on influx and efflux of labelled substrate and (2) by testing some predictions of the theory of Lieb and Stein [1974) Biochim. Biophys. Acta 373, 165-177). The carrier was trans-inhibited by T3 on both sides of the membrane. Under zero-trans conditions, the carrier displayed asymmetrical properties, the Michaelis constant and the maximal velocity being more than 6-times higher for influx than for efflux. Under equilibrium-exchange conditions, the Michaelis constant was lower than the zero-trans values, as expected when trans-inhibition occurs. This kinetic behaviour is consistent with a carrier which is accessible to T3 simultaneously from both sides of the erythrocyte membrane.
通过以下方式研究了经洗涤的大鼠红细胞中载体介导的3,5,3'-三碘-L-甲状腺原氨酸（T3）转运的动力学特性：（1）研究未标记的T3对标记底物流入和流出的影响；（2）检验Lieb和Stein [1974年，《生物化学与生物物理学报》373卷，165 - 177页]理论的一些预测。T3在膜两侧对载体均有反式抑制作用。在零转运条件下，载体表现出不对称特性，流入的米氏常数和最大速度比流出时高6倍以上。在平衡交换条件下，米氏常数低于零转运值，这在发生反式抑制时是预期的。这种动力学行为与一种可同时从红细胞膜两侧接触T3的载体相一致。
