Cerebral oxygen utilization analyzed by the use of oxygen-17 and its nuclear magnetic resonance

In order to assess the usefulness of oxygen-17, a stable isotope of oxygen, oxygen-17, was administered to rats for studying cerebral oxygen utilization, and the produced metabolic water was detected by 17O-NMR spectroscopy in vitro and an 1H-NMR imaging system in vivo. In the vitro study, the increment in signal amplitude of oxygen-17 was observed in the brain extracted from rats that inhaled oxygen-17 gas. The in vivo study demonstrated that there were changes in the 1H-NMR image intensity of brain of rats that inhaled oxygen-17 gas. These facts indicate that oxygen-17 can serve as a tracer in the study of cerebral oxygen utilization.