Basal Q10 for Cerebral Metabolic Rate for Oxygen (CMRO2) in Rats

  • R. Klementavicius
  • E. M. Nemoto
  • H. Yonas
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 388)


The effect of hypothermia on cerebral metabolic rate for oxygen (CMRO2) is well established and is effectively expressed by the Q10, i.e. the ratio of total CMRO2 (TCMRO2) over a temperature range of 10°C. Reported values for Q10 vary from 2.3 (Michenfelder and Theye, 1968) in dogs to 4.4 in man (Cohen et al, 1964), reflecting the controversy on the “true” value of Q10. Reports over the last decade investigating the metabolic effects of mild and moderate hypothermia on the brain and their protective effects during global and focal ischemia relative to those of barbiturates, have questioned the notion as to whether the predominant mechanism of brain protection by hypothermia or barbiturates is simply attributable to a reduction of CMRO2. We previously reported a Q10 of 2.5 for TCMRO2 in rats but also showed that hypothermia depressed active CMRO2 (ACMRO2) i.e. thiopental suppressible or EEG associated CMRO2 less than basal CMRO2 which is utilized for maintaining cell integrity and viability (Nemoto et al, 1993). On the basis of these results, we hypothesized that Q10 for BCMRO2 differs from that for ACMRO2 and determined the Q10for BCMRO2 in rats


Cerebral Blood Flow Mean Arterial Pressure Cardiopulmonary Bypass Mild Hypothermia Moderate Hypothermia 
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Copyright information

© Plenum Press, New York 1996

Authors and Affiliations

  • R. Klementavicius
    • 1
  • E. M. Nemoto
    • 1
  • H. Yonas
    • 1
  1. 1.Departments of Anesthesiology/CCM and Neurological SurgeryUniversity of PittsburghPittsburghUSA

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