Hôpitaux Universitaires de Strasbourg, Biophysics and Nuclear Medicine Department, Hôpital de Hautepierre, 1 avenue Molière, 67098 Strasbourg Cedex, France.
J Neurosci Methods. 2011 Sep 30;201(1):89-97. doi: 10.1016/j.jneumeth.2011.07.014. Epub 2011 Jul 23.
High resolution magic-angle spinning (HRMAS) NMR spectroscopy is a well established technique for ex vivo metabolite investigations but experimental factors such as ischemic delay or mechanical stress due to continuous spinning deserve further investigations. Cortical brain samples from rats that underwent ultrafast in vivo microwave irradiation (MWp group) were compared to similar samples that underwent standard nitrogen freezing with and without exposure to domestic microwaves (FN and FN+MWd groups). One dimensional (1)H HRMAS NMR spectra were acquired and 16 metabolites of interest were quantified. Within each group 3 samples underwent long lasting acquisition (up to 15 h). Statistically significant differences in metabolite concentrations were observed between groups for metabolites associated to post mortem biochemical changes and/or anaerobic glycolysis including several neurotransmitters. Spectral assessment over time showed a drastic reduction of biochemical variations in both MW groups. Only 2/16 metabolites exhibited significant signal variations after 15 h of continuous spinning and acquisition in the MWp group. This number increased to 10 in the FN group. We confirmed limited anaerobic metabolism and post mortem degradation after ultra fast in vivo MW irradiation. Furthermore, spectra obtained after MWp and MWd irradiation exhibited an extremely stable spectral pattern over extended periods of continuous acquisition.
高分辨魔角旋转（HRMAS）NMR 光谱学是一种成熟的用于离体代谢物研究的技术，但由于连续旋转引起的缺血延迟或机械应激等实验因素值得进一步研究。对接受超快体内微波辐射（MWp 组）的大鼠皮质脑样本进行了比较，这些样本与经历了标准氮气冷冻但未暴露于家用微波辐射的类似样本（FN 和 FN+MWd 组）进行了比较。采集了一维（1）H HRMAS NMR 光谱，并对 16 种感兴趣的代谢物进行了定量分析。在每个组中，有 3 个样本进行了长时间采集（长达 15 小时）。结果显示，与死后生化变化和/或无氧糖酵解相关的代谢物在各组之间存在统计学上的显著差异，包括几种神经递质。随着时间的推移，MW 组的生化变化明显减少。在 MWp 组中，只有 2/16 种代谢物在连续旋转和采集 15 小时后表现出显著的信号变化。在 FN 组中，这个数字增加到 10。我们证实了超快体内 MW 辐射后有限的无氧代谢和死后降解。此外，在 MWp 和 MWd 辐射后获得的光谱在长时间连续采集期间表现出极其稳定的光谱模式。
