IVERSEN L L
Br J Pharmacol Chemother. 1963 Dec;21(3):523-37. doi: 10.1111/j.1476-5381.1963.tb02020.x.
The uptake of noradrenaline by the isolated perfused rat heart was studied after perfusion with a medium containing various concentrations of (+/-)-[(3)H]-noradrenaline. Simultaneous measurement of the uptake of [(3)H]-noradrenaline and of the net increase in the noradrenaline content of the heart showed that [(3)H]-noradrenaline entering the heart both increased the tissue content and exchanged with endogenous noradrenaline. A large part (about 75%) of the endogenous noradrenaline pool, however, exchanged very slowly if at all with exogenous noradrenaline. The initial rates of noradrenaline uptake satisfied Michaelis-Menten kinetics with a Km for (+/-)-noradrenaline of 6.64x10(-7) M. Further analysis of the uptake process indicated that noradrenaline entered into at least two intracellular pools at different rates. Measurement of the initial rates of noradrenaline uptake during perfusion with various concentrations of nonradioactive (+)- and (-)-noradrenaline showed that the uptake process exhibited stereochemical specificity. The Km values for (+)- and (-)-noradrenaline were 13.9x10(-7) and 2.66x10(-7) M respectively. Cocaine acted as a potent competitive inhibitor of noradrenaline uptake. This finding suggested that diffusion did not play any significant role in the entry of noradrenaline into the tissue.
在用含有不同浓度（±）-[³H]-去甲肾上腺素的培养基灌注后，研究了离体灌注大鼠心脏对去甲肾上腺素的摄取。同时测量[³H]-去甲肾上腺素的摄取以及心脏中去甲肾上腺素含量的净增加量，结果表明进入心脏的[³H]-去甲肾上腺素既增加了组织含量，又与内源性去甲肾上腺素进行了交换。然而，很大一部分（约75%）内源性去甲肾上腺素库与外源性去甲肾上腺素的交换非常缓慢，甚至根本不交换。去甲肾上腺素摄取的初始速率符合米氏动力学，（±）-去甲肾上腺素的Km值为6.64×10⁻⁷ M。对摄取过程的进一步分析表明，去甲肾上腺素以不同速率进入至少两个细胞内池。在用不同浓度的非放射性（+）-和（-）-去甲肾上腺素灌注期间测量去甲肾上腺素摄取的初始速率，结果表明摄取过程具有立体化学特异性。（+）-和（-）-去甲肾上腺素的Km值分别为13.9×10⁻⁷和2.66×10⁻⁷ M。可卡因是去甲肾上腺素摄取的强效竞争性抑制剂。这一发现表明，扩散在去甲肾上腺素进入组织的过程中没有起到任何显著作用。
