Stefanovich V, Gojowczyk G
Neurochem Res. 1981 Apr;6(4):431-40. doi: 10.1007/BF00963858.
Microvessels were isolated from a bovine cortex and the transport of glucose was investigated by using 2-deoxy-D-[3H]glucose (2-DG). The apparent Km for 2-DG transport was 118 microM and therefore indicates a significant high affinity for the substrate. The inhibition of 2-DG uptake by D-glucose showed an apparent Ki of 222 microM. Other sugars, e.g., 3-methyl-D glucose and D-fructose, also inhibited the 2-DG uptake by 60.6 and 36.0%, respectively. Phloretin (1 X 10(-3) M) inhibited the 2-DG transport more than phlorizin (83.7 vs. 53.8%). Ouabain (1 and 5 X 10(-4) M) did not inhibit the uptake of 2-DG but 2,4-dinitrophenol (1 X 10(-4) M) did (78.0%). The uptake of 2-DG could not be demonstrated in homogenized microvessels. Adenine nucleotides (conc. 2 mM) had various effects on the 2-DG uptake by microvessels. ATP inhibited the uptake by 20.7%, ADP was virtually without effect, and AMP stimulated the uptake of 2-DG by 8.5%. It was also found that the decrease of adenylate energy charge favors the uptake of 2-DG. All these findings suggest that, in cerebral microvessels of a bovine cortex, 2-DG is apparently transported by a specific, carrier-mediated transport system.
从小牛大脑皮层分离出微血管，并用2-脱氧-D-[3H]葡萄糖（2-DG）研究葡萄糖的转运。2-DG转运的表观米氏常数（Km）为118微摩尔，因此表明对底物具有显著的高亲和力。D-葡萄糖对2-DG摄取的抑制作用显示表观抑制常数（Ki）为222微摩尔。其他糖类，如3-甲基-D-葡萄糖和D-果糖，也分别抑制2-DG摄取60.6%和36.0%。根皮素（1×10⁻³ M）对2-DG转运的抑制作用大于根皮苷（83.7%对53.8%）。哇巴因（1和5×10⁻⁴ M）不抑制2-DG的摄取，但2,4-二硝基苯酚（1×10⁻⁴ M）可抑制（78.0%）。在匀浆的微血管中未显示出2-DG的摄取。腺嘌呤核苷酸（浓度2 mM）对微血管摄取2-DG有多种影响。ATP抑制摄取20.7%，ADP几乎无作用，而AMP刺激2-DG摄取8.5%。还发现腺苷酸能荷的降低有利于2-DG的摄取。所有这些发现表明，在小牛大脑皮层的脑微血管中，2-DG显然是通过一种特异性的、载体介导的转运系统进行转运。
