Kilberg M S
J Membr Biol. 1982;69(1):1-12. doi: 10.1007/BF01871236.
Improvements in the collagenase perfusion techniques have made isolated rat hepatocytes a popular model in which to study hepatic function. Our knowledge of hepatic amino acid transport has been advanced as a result of this methodology. Translocation across the hepatocyte plasma membrane can, in some instances, represent the rate-limiting step in the overall metabolism of certain amino acids. Furthermore, regulation of amino acid uptake by hepatocytes appears to play a role in diabetes, and perhaps in malignant transformation. Comparisons between normal adult hepatocytes and several hepatoma cell lines show basic differences in amino acid transport. There are at least eight distinct systems in normal hepatocytes for transport of the hormones. Systems A and N exhibit enhanced uptake rates after the cells have been maintained in the absence of extracellular amino acids, a phenomenon termed adaptive control. Further studies using isolated hepatocytes will increase our basic understanding of membrane transport processes and their regulation.
胶原酶灌注技术的改进使分离的大鼠肝细胞成为研究肝功能的常用模型。由于这种方法，我们对肝脏氨基酸转运的认识有了进展。在某些情况下，跨肝细胞质膜的转运可能是某些氨基酸整体代谢中的限速步骤。此外，肝细胞对氨基酸摄取的调节似乎在糖尿病中起作用，也许在恶性转化中也起作用。正常成年肝细胞与几种肝癌细胞系之间的比较显示出氨基酸转运的基本差异。正常肝细胞中至少有八个不同的激素转运系统。在细胞维持在无细胞外氨基酸的状态后，系统A和N表现出增强的摄取率，这种现象称为适应性控制。使用分离的肝细胞进行的进一步研究将增加我们对膜转运过程及其调节的基本理解。
