Cerebral Oxygenation of the Cortex and Striatum Following Normobaric Hyperoxia and Mild Hypoxia in Rats by EPR Oximetry Using Multi-Probe Implantable Resonators

  • Huagang HouEmail author
  • Hongbin Li
  • Ruhong Dong
  • Sriram Mupparaju
  • Nadeem Khan
  • Harold Swartz
Conference paper
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 701)


Multi-site electron paramagnetic resonance (EPR) oximetry, using multiprobe implantable resonators, was used to measure the partial pressure of oxygen (pO2) in the brains of rats following normobaric hyperoxia and mild hypoxia. The cerebral tissue pO2 was measured simultaneously in the cerebral cortex and striatum in the same rats before, during, and after normobaric hyperoxia and mild hypoxia challenges. The mean baseline tissue pO2 values were not significantly different between the cortex and striatum.During 30 min of 100%O2 inhalation, a statistically significant increase in tissue pO2 of all four sites was observed, however, the tissue pO2 of the striatum area was significantly higher than in the forelimb area of the cortex. Brain pO2 significantly decreased from the baseline value during 15 min of 15% O2 challenge.No differences in the recovery of the cerebral cortex and striatum pO2 were observed when the rats were allowed to breathe 30% O2. It appears that EPRoximetry using implantable resonators can provide information on pO2 under the experimental conditions needed for such a study. The levels of pO2 that occurred in these experiments are readily resolvable bymulti-siteEPRoximetrywithmulti-probe resonators. In addition, the ability to simultaneouslymeasure the pO2 in several areas of the brain provides important information that could potentially help differentiate the pO2 changes that can occur due to global or local mechanisms.


Electron Paramagnetic Resonance Electron Paramagnetic Resonance Spectrum Cerebral Oxygenation Electron Paramagnetic Resonance Spectrometer Mild Hypoxia 
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  1. 1.
    Hou, H., Grinberg, O, Williams, B, Grinberg, S, Yu, H, Alvarenga, DL, Wallach, H, Buckey, J, Swartz, HM. (2007) Effect of oxygen therapy on brain damage and cerebral pO2 in transient focal cerebral ischemia in the rat.. Physiol Meas 28:963-76PubMedCrossRefGoogle Scholar
  2. 2.
    Hou, H., Grinberg, O.Y., Grinberg, S.A., et al. (2005) Cerebral tissue oxygenation in reversible focal ischemia in rats: multi-site EPR oximetry measurements. Physiol Meas 26:131-41PubMedCrossRefGoogle Scholar
  3. 3.
    Hou, H., Khan, N., O’Hara, J.A., et al. (2005) Increased oxygenation of intracranial tumors by efaproxyn (efaproxiral), an allosteric hemoglobin modifier: In vivo EPR oximetry study. Int J Radiat Oncol Biol Phys 61:1503-9PubMedCrossRefGoogle Scholar
  4. 4.
    Li, H., Hou, H., Sucheta, A., et al. (2010) Implantable resonators - a technique for repeated measurements of oxygen at multiple deep sites with in vivo EPR Adv Exp Med Biol 662:265-72Google Scholar
  5. 5.
    Liu, K., Gast P, and Moussavi, M. (1993) Lithium phthalocyanine: A probe for electron paramagnetic resonance oximetry in viable biological systems. Proc Natl Acad Sci USA 90:5438-42PubMedCrossRefGoogle Scholar
  6. 6.
    Swartz,H.M., Clarkson, R.B. . (1998) The measurement of oxygen in vivo using EPR techniques.. Physics in Medicine & Biology 43:1957-75CrossRefGoogle Scholar
  7. 7.
    Smirnov, A.I., Norby, S.W., Clarkson, R.B., et al. (1993) Simultaneous multi-site EPR spectroscopy in vivo. Magn Reson Med 30:213-20PubMedCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Huagang Hou
    • 1
    Email author
  • Hongbin Li
  • Ruhong Dong
  • Sriram Mupparaju
  • Nadeem Khan
  • Harold Swartz
  1. 1.EPR Center for Viable Systems, Department of Diagnostic RadiologyDartmouth Medical SchoolHanoverUSA

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