Chan P, Langston J W, Irwin I, DeLanney L E, Di Monte D A
California Parkinson's Foundation, San Jose.
J Neurochem. 1993 Aug;61(2):610-6. doi: 10.1111/j.1471-4159.1993.tb02165.x.
The effects of 2-deoxyglucose (2-DG), an inhibitor of the uptake and use of glucose, on ATP loss caused by the neurotoxicant 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) were determined in the mouse brain. 2-DG alone had no effect on brain ATP levels, but when administered 30 min before MPTP exposure, 2-DG significantly enhanced MPTP-induced ATP reduction. This was reflected as an increase in ATP loss in the striatum (from 15 to 27%) as well as a significant decrease in ATP in the cerebellar cortex, an area of the brain that was not affected after exposure to MPTP alone. In mice pretreated with 2-DG, striatal ATP levels remained significantly decreased for > 8 h after MPTP administration. In contrast, ATP levels in the cerebellar cortex returned to normal values within 4 h from MPTP exposure. Mazindol, a catecholamine uptake blocker, completely protected against MPTP-induced loss of striatal ATP in the absence of 2-DG, but it only partially prevented striatal ATP decrease after administration of both 2-DG and MPTP; mazindol was also ineffective in protecting against ATP loss caused by 2-DG and MPTP in the cerebellar cortex. 2-DG/MPTP-induced ATP loss appeared to be associated with the presence of the 1-methyl-4-phenylpyridinium (MPP+) metabolite because (1) the pattern of ATP recovery in the striatum and cerebellar cortex appeared to reflect the pattern of MPP+ clearance from these areas of the brain (i.e., significant MPP+ levels persisted longer in the striatum than in the cerebellar cortex), and (2) ATP decrease was completely prevented by blocking the conversion of MPTP to MPP+ with the monoamine oxidase B inhibitor deprenyl.(ABSTRACT TRUNCATED AT 250 WORDS)
在小鼠脑中测定了葡萄糖摄取和利用抑制剂2-脱氧葡萄糖(2-DG)对神经毒素1-甲基-4-苯基-1,2,3,6-四氢吡啶(MPTP)所致ATP损失的影响。单独使用2-DG对脑ATP水平无影响,但在MPTP暴露前30分钟给予2-DG时,2-DG显著增强了MPTP诱导的ATP降低。这表现为纹状体中ATP损失增加(从15%增至27%)以及小脑皮质中ATP显著减少,而小脑皮质是单独暴露于MPTP后未受影响的脑区。在用2-DG预处理的小鼠中,MPTP给药后纹状体ATP水平在8小时以上仍显著降低。相比之下,小脑皮质中的ATP水平在MPTP暴露后4小时内恢复到正常水平。去甲肾上腺素摄取阻滞剂吗茚酮在不存在2-DG时能完全防止MPTP诱导的纹状体ATP损失,但在同时给予2-DG和MPTP后,它只能部分阻止纹状体ATP降低;吗茚酮在防止2-DG和MPTP引起的小脑皮质ATP损失方面也无效。2-DG/MPTP诱导的ATP损失似乎与1-甲基-4-苯基吡啶离子(MPP+)代谢物的存在有关,因为(1)纹状体和小脑皮质中ATP恢复的模式似乎反映了MPP+从这些脑区清除的模式(即纹状体中显著的MPP+水平持续时间比小脑皮质更长),以及(2)通过单胺氧化酶B抑制剂丙炔苯丙胺阻断MPTP向MPP+的转化可完全防止ATP降低。(摘要截断于250字)