Halban P A, Praz G A, Wollheim C B
Biochem J. 1983 May 15;212(2):439-43. doi: 10.1042/bj2120439.
Glucose metabolism and insulin release were studied in isolated rat islets and in an insulin-producing rat cell-line (RINm5F). Intact islets displayed two components of glucose utilization, with glucose stimulation of insulin release being associated with the high-Km component (reflecting glucokinase-like activity). Glucose failed to stimulate insulin release from RINm5F cells, which only displayed a single low-Km component of glucose utilization. Only low-Km (hexokinase-like) glucose-phosphorylating activity was found for disrupted RINm5F cells. These changes in glucose metabolism may contribute towards the failure of glucose to stimulate insulin release from RINm5F cells.
在分离的大鼠胰岛和一个产生胰岛素的大鼠细胞系(RINm5F)中研究了葡萄糖代谢和胰岛素释放。完整的胰岛表现出葡萄糖利用的两个组分,葡萄糖刺激胰岛素释放与高Km组分相关(反映类似葡萄糖激酶的活性)。葡萄糖不能刺激RINm5F细胞释放胰岛素,该细胞仅表现出葡萄糖利用的单一低Km组分。对于破碎的RINm5F细胞,仅发现低Km(类似己糖激酶)的葡萄糖磷酸化活性。葡萄糖代谢的这些变化可能导致葡萄糖不能刺激RINm5F细胞释放胰岛素。