Gardiner M, Smith M L, Kågström E, Shohami E, Siesjö B K
J Cereb Blood Flow Metab. 1982 Dec;2(4):429-38. doi: 10.1038/jcbfm.1982.49.
The effects of hypoxaemia on regional cerebral blood flow (CBF) and brain cortical metabolite concentrations were investigated at different blood glucose concentrations in rats under nitrous oxide anaesthesia. Tissue hypoxia of 15-min duration was induced by a combination of arterial hypoxaemia, hypotension, and clamping of the right carotid artery. Blood glucose concentrations were manipulated by varying the food intake in the 24 h before the experiment, and by glucose administration. Cortical CBF doubled during hypoxia on the intact side, but did not differ significantly from control values on the clamped side. In the clamped hemisphere there was a substantial decrease in adenylate energy charge. At brain tissue glucose concentration of 1 mumol g-1 and above, there was an inverse correlation between adenylate energy charge and brain lactate concentration. In starved animals with mean brain glucose of 0.32 +/- 0.00 mumol g-1, lactate concentration was significantly lower, in spite of equally severe disruption of energy state. Recovery of brain adenylate energy charge was worse in fed and glucose-infused groups than in the fasted group. These results demonstrate that limitation of substrate supply during severe hypoxia in the rat allows enhanced recovery of brain energy metabolism following the hypoxic episode.
在一氧化二氮麻醉下，研究了不同血糖浓度时低氧血症对大鼠局部脑血流量（CBF）和脑皮质代谢物浓度的影响。通过动脉低氧血症、低血压和夹闭右颈动脉相结合的方式诱导持续15分钟的组织缺氧。通过在实验前24小时改变食物摄入量以及给予葡萄糖来控制血糖浓度。缺氧期间，完整侧的皮质CBF增加了一倍，但夹闭侧与对照值无显著差异。在夹闭的半球中，腺苷酸能荷大幅下降。在脑组织葡萄糖浓度为1 μmol g-1及以上时，腺苷酸能荷与脑乳酸浓度呈负相关。在平均脑葡萄糖为0.32±0.00 μmol g-1的饥饿动物中，尽管能量状态同样严重受损，但乳酸浓度显著较低。喂食和输注葡萄糖组的脑腺苷酸能荷恢复情况比禁食组更差。这些结果表明，大鼠在严重缺氧期间底物供应受限，使得缺氧发作后脑能量代谢的恢复增强。
