NA+-DEPENDENT GLUTAMINE TRANSPORT IN THE LIVER OF TUMOR-BEARING RATS

被引：16

作者：

DUDRICK, PS ^{[1
]}

INOUE, Y ^{[1
]}

ESPAT, NJ ^{[1
]}

SOUBA, WW ^{[1
]}

机构：

[1] UNIV FLORIDA,COLL MED,DEPT SURG,DIV SURG METAB NUTR,GAINESVILLE,FL 32611

来源：

SURGICAL ONCOLOGY-OXFORD | 1993年 / 2卷 / 03期

关键词：

CANCER; GLUTAMINE; HEPATIC SYSTEM-N; LIVER; TRANSPORT;

D O I：

10.1016/0960-7404(93)90008-M

中图分类号：

R73 [肿瘤学];

学科分类号：

100214 ;

摘要：

In rats with advanced malignant disease, the liver extracted circulating glutamine at a ratio three times faster than the liver of control non-tumour-bearing animals. This augmented uptake occurred in spite of a fall in circulating glutamine levels, implying an increase in hepatocyte plasma membrane transport. Na+-dependent glutamine transport activity (System N) was increased nearly two-fold in hepatocyte plasma membrane vesicles from tumour-bearing rats; this increase in System N activity was proportional to tumour size and was due to an increase in carrier V(max) with no change in carrier affinity. Measurement of System N activity in isolated hepatocytes incubated with serum from tumour-bearing rats demonstrated a significant increase in glutamine transport compared with cells incubated with serum from control rats. These data indicate that the liver of rats with advanced malignant disease displays accelerated glutamine consumption. This increased uptake is due, in part, to enhanced carrier-mediated transport activity, and is mediated by a circulating factor(s) that is not present (or inactive) in non-tumour-bearing controls.

引用

页码：205 / 215

页数：11

共 29 条

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