31P Nuclear magnetic resonance spectroscopy studies on global cerebral cellular energy metabolism following acute oxygen poisoning in rats

Objective: To evaluate cerebral cellular energy metabolism and pH in the rat global cerebral cellular following acute oxygen poisoning. Methods: All ~31P NMR spectra were performed on a high-field, 4. 7 T, NMR spectroscopic imag- ing system using a ~31P/1~H double-tuned surface coil. Intracellular pH were determined according to the spectra of pi. Results: Phosphocreatine to inorganic phosphate (PCr/Pi ), PCr to gamma adenosine triphosphate (PCr/γ-ATP ) and adenosine triphosphate to inorganic phosphate (β-ATP/Pi) decreased compared with the corresponding ratios in control group in the en- tire brain at 1 and 3 h after exposing HBO. At 5 h, no significant decrease of the ratios was found. At 24 h, the ratios were decreased significantly again. At 72 h, the ratios prestored to normal level. Intracellular pH was significantly decreased at 1 and 3 h after exposing HBO. At 5 h, no significant change of the intracellular pH was found. At 24 h, the pH was increased significantly. At 48 h, the pH restored to normal level. Conclusion: There are energy failure and intracellular acidosis and alkalosis in cerebral cellular after oxygen poisoning in rats.