Abstract
Fresh rat brain slices were incubated with [ 18F]2-fluoro-2-deoxy- d-glucose ([ 18F]FDG) in oxygenated Krebs–Ringer solution at 36 °C, and the fractional rate constant (= k 3*) of [ 18F]FDG proportional to the cerebral glucose metabolic rate in white matter and gray matter was investigated with positron autoradiography. In both white matter and gray matter, the k 3* value with ≥20 min hypoxia was markedly lower than the unloaded control value, indicating irreversible hypoxic injury. Next, the neuroprotective effect against hypoxia induced by the addition of an N-methyl- d-aspartate receptor antagonist or a free radical scavenger was assessed by determining whether a decrease in the k 3* value after hypoxia loading was prevented. In gray matter, both agents exhibited a neuroprotective effect against 20 min hypoxia. In white matter, however, only the free radical scavenger was effective. These results suggest a similarity in the degree of vulnerability to hypoxia between white matter and gray matter as well as a difference in the developmental mechanism of hypoxic injury, i.e. the involvement of both glutamate and free radicals in gray matter, and the more selective involvement of free radicals in white matter.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.