Manuel y Keenoy B, Zähner D, Malaisse W J
Laboratoire de Médecine Expérimentale, Faculté de Médecine Erasme, Université Libre de Bruxelles, Belgium.
Biochem J. 1992 Dec 1;288 ( Pt 2)(Pt 2):433-8. doi: 10.1042/bj2880433.
When rat erythrocytes were preincubated with 2-deoxy-D-glucose, the generation of both 3H-labelled acidic metabolites and 3HOH from D-[5-3H]glucose, the total production of L-lactate, and the generation of 14CO2, 14C-labelled acidic metabolites and 14C-labelled lactate from D-[1-14C]glucose or D-[U-14C]glucose were all lower than in erythrocytes preincubated in the absence of a hexose or in the presence of 3-O-methyl-D-glucose. However, preincubation with 2-deoxy-D-glucose failed to decrease the generation of 3H-labelled acidic metabolites and L-[3-3H]lactate from D-[2-3H]glucose, while decreasing the production of 3HOH more severely from D-[2-3H]glucose than from D-[5-3H]glucose. This may be attributable not solely to inhibition of D-glucose phosphorylation by 2-deoxy-D-glucose and 2-deoxy-D-glucose 6-phosphate, but also to inhibition by 2-deoxy-D-glucose 6-phosphate of hexose 6-phosphate interconversion in the reaction catalysed by phosphoglucoisomerase, as also observed with the purified enzyme. The generation of 3HOH from D-[2-3H]glucose should therefore be considered as a tool to assess the efficiency of interconversion of hexose 6-phosphates in the reaction catalysed by phosphoglucoisomerase, rather than to estimate D-glucose phosphorylation rate.
当大鼠红细胞与2-脱氧-D-葡萄糖预孵育时，D-[5-³H]葡萄糖生成³H标记的酸性代谢产物和³H₂O、L-乳酸的总生成量，以及D-[1-¹⁴C]葡萄糖或D-[U-¹⁴C]葡萄糖生成¹⁴CO₂、¹⁴C标记的酸性代谢产物和¹⁴C标记的乳酸的量均低于在无己糖预孵育或有3-O-甲基-D-葡萄糖存在下预孵育的红细胞。然而，用2-脱氧-D-葡萄糖预孵育未能降低D-[2-³H]葡萄糖生成³H标记的酸性代谢产物和L-[3-³H]乳酸的量，同时与D-[5-³H]葡萄糖相比，更严重地降低了D-[2-³H]葡萄糖生成³H₂O的量。这可能不仅归因于2-脱氧-D-葡萄糖和2-脱氧-D-葡萄糖6-磷酸对D-葡萄糖磷酸化的抑制，还归因于2-脱氧-D-葡萄糖6-磷酸对磷酸葡萄糖异构酶催化反应中己糖6-磷酸相互转化的抑制，这在纯化酶中也有观察到。因此，D-[2-³H]葡萄糖生成³H₂O应被视为评估磷酸葡萄糖异构酶催化反应中己糖6-磷酸相互转化效率的工具，而不是估计D-葡萄糖磷酸化速率的工具。
