[Successive detection of cortex oxygen partial pressure with oxygen microelectrodes in cats]

Brain tissue PO2 (PtO2) was successively measured with the new polarographic oxygen microelectrodes in the parietal cortex of ketamine anesthetized cats. This type of oxygen microelectrodes was made from pure platinum wire 0.5 microns in diameter pulled in glass with tip diameter of less than 1.0 micron. Results showed that PtO2 in the superficial gray matter (0-1,000 microns) was markedly higher than that in the white matter (1,001-3,000, 3,001-5,000 microns) in 10 cats. No significant change was observed during successive detecting of PtO2 within 3.0 hours in the cats. It was suggested that we can directly understand the oxygen supply and metabolism of living brain tissue by using the new oxygen microelectrodes.