GLUT-1 and GLUT-2 mRNA, protein, and glucose transporter activity in cultured fetal and adult hepatocytes.
GLUT-1 and GLUT-2 mRNA, protein, and glucose transporter activity in cultured fetal and adult hepatocytes.
复制标题
培养的胎儿和成人肝细胞中的 GLUT-1 和 GLUT-2 mRNA、蛋白质和葡萄糖转运蛋白活性。
DOI：
10.1152/ajpendo.1994.267.1.e88
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
Rhoads,DB
中科院分区：
文献类型：
--
作者：
Levitsky,LL;Zheng,Q;Mink,K;Rhoads,DB
To understand glycogenesis in the fetal hepatocyte, we examined glucose transport in cultured fetal and adult male rat hepatocytes. GLUT-1 mRNA was detected in fetal hepatocytes at isolation but in adult hepatocytes only after culture. GLUT-1 mRNA was more abundant in fetal than in adult hepatocytes (P < 0.005). GLUT-1 protein paralleled its message. GLUT-2 mRNA was more abundant in adult than in fetal hepatocytes (P < 0.05), and abundance did not change during culture, but GLUT-2 protein was discordantly regulated. There was more GLUT-2 protein in fetal hepatocytes at 45 h (P < 0.025). An Eadie-Hofstee plot of 3-O-methylglucose transport appeared to have two linear components. One component was presumed to be GLUT-1 [variable Michaelis constant (Km) approximating 6-8 mM, maximal uptake rate (Vmax) for fetal vs. adult hepatocytes 106 vs. 35 nmol.min-1.mg protein-1], and a second was presumed to be GLUT-2 (Km of 23 mM, Vmax for fetal vs. adult hepatocytes 198 vs. 92 nmol.min-1.mg protein-1). Early phosphorylation of 2-deoxyglucose was greater in fetal than in adult hepatocytes, but transport was always greater than phosphorylation. Increased expression of both GLUT-1 and GLUT-2 by fetal hepatocytes permits greater glucose uptake and positions the fetal rat hepatocyte for efficient glycogenesis at low plasma glucose concentration.
