Misra C H
J Neurosci Res. 1980;5(6):507-14. doi: 10.1002/jnr.490050606.
The in vitro uptake of [35S] cysteine was studied in crude synaptosomal preparation of the cerebral cortex of rat. The accumulation of cysteine was found to be temperature- and time-dependent. It was linear at least for four minutes at 37 C with characteristics of saturable kinetics. Uptake of cysteine was Na+- and K+-dependent. Increasing the Na+ ion concentration increased the accumulation of cysteine in synaptosomal preparations; unlike the Na+ ion, an increase was accumulated against concentration gradients by a saturable mechanism. Double reciprocal plot of the cysteine uptake suggests two types of affinity systems, with Km values for the high-affinity uptake of about 12.2 microM and for the low-affinity uptake of about 4 mM. The high-affinity uptake was also significantly inhibited by ouabain, a potent inhibitor of the Na+-K+-dependent ATPase, and other metabolic inhibitors. The results of the effects of cysteine analogues and uptake also suggested that it is a substrate-specific high-affinity uptake system for cysteine.
在大鼠大脑皮层粗制突触体标本中研究了[35S]半胱氨酸的体外摄取。发现半胱氨酸的积累具有温度和时间依赖性。在37℃下至少4分钟呈线性，具有饱和动力学特征。半胱氨酸的摄取依赖于Na+和K+。增加Na+离子浓度会增加突触体标本中半胱氨酸的积累；与Na+离子不同，半胱氨酸是通过一种可饱和机制逆浓度梯度积累的。半胱氨酸摄取的双倒数图表明存在两种亲和力系统，高亲和力摄取的Km值约为12.2 microM，低亲和力摄取的Km值约为4 mM。高亲和力摄取也受到哇巴因（一种Na+-K+依赖性ATP酶的有效抑制剂）和其他代谢抑制剂的显著抑制。半胱氨酸类似物的作用结果和摄取情况还表明，这是一个半胱氨酸底物特异性的高亲和力摄取系统。
