Brooks K J, Porteous R, Bachelard H S
Division of Biochemistry Sciences, United Medical School, London, England.
J Neurochem. 1989 Feb;52(2):604-10. doi: 10.1111/j.1471-4159.1989.tb09162.x.
Changes in high-energy phosphate metabolites and the intracellular pH (pHi) were monitored in cerebral tissue during periods of hypoglycaemia and hypoxia using 31P nuclear magnetic resonance spectroscopy. Superfused brain slices were loaded with deoxyglucose at a concentration shown not to impair cerebral metabolism, and the chemical shift of the resulting 2-deoxyglucose-6-phosphate (DOG6P) peak was used to monitor the pHi. In some experiments with low circulating levels of Pi, the intracellular Pi was visible and indicated a pH identical to that of DOG6P, an observation validating its use as an indicator of pHi in cerebral tissue. The pHi was found to be unchanged during moderate hypoglycaemia; however, mild hypoxia (PO2 = 16.4 kPa) and severe hypoglycaemia produced marked reductions from the normal of 7.2 to 6.8 and 7.0, respectively. Hypoglycaemia caused a fall in the level of both phosphocreatine (PCr) and ATP, whereas hypoxia affected PCr alone, as shown previously. However, the fall in pHi was similar during the two insults, thus indicating that the change in pH is not directly linked to lactate production or to the creatine kinase reaction.
利用31P核磁共振波谱技术，在低血糖和缺氧期间监测脑组织中高能磷酸代谢物和细胞内pH值（pHi）的变化。将超融合脑片用脱氧葡萄糖加载，其浓度显示不会损害脑代谢，并利用所得6-磷酸-2-脱氧葡萄糖（DOG6P）峰的化学位移来监测pHi。在一些循环磷水平较低的实验中，细胞内磷是可见的，并且显示其pH值与DOG6P相同，这一观察结果验证了其作为脑组织中pHi指标的用途。发现在中度低血糖期间pHi没有变化；然而，轻度缺氧（PO2 = 16.4 kPa）和严重低血糖分别使pHi从正常的7.2显著降至6.8和7.0。低血糖导致磷酸肌酸（PCr）和ATP水平下降，而缺氧如先前所示仅影响PCr。然而，在这两种损伤期间pHi的下降是相似的，因此表明pH值的变化与乳酸产生或肌酸激酶反应没有直接联系。
