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Correspondence  |   November 2008
Role of Hydrogen Peroxide in Propofol Restoration of Microvascular Function Impaired by High Glucose
Author Affiliations & Notes
  • Hiroyuki Kinoshita, M.D., Ph.D.
    *
  • *Wakayama Medical University, Wakayama, Japan.
Article Information
Correspondence
Correspondence   |   November 2008
Role of Hydrogen Peroxide in Propofol Restoration of Microvascular Function Impaired by High Glucose
Anesthesiology 11 2008, Vol.109, 930-931. doi:10.1097/ALN.0b013e3181897c8c
Anesthesiology 11 2008, Vol.109, 930-931. doi:10.1097/ALN.0b013e3181897c8c
In Reply:—  We appreciate Dr. Xia’s comments regarding our article.1 As far as we understand, the comments can be summarized into two issues, including why we did not adopt the term “superoxide production” in the title of our article and why we focused our study on levels of superoxide, but not hydrogen peroxide, induced by the high concentration of glucose. We agree with Dr. Xia’s concern that oxidative stress results from an imbalance between the formation and the neutralization of oxidants. This is why we mentioned in the title of our article that propofol confers a decrease in oxidative stress, but not superoxide production, because we did not find definite evidence to support whether the effect of propofol on levels of superoxide in the rat brain slice is due to the inhibitory effect of this intravenous anesthetic on the formation or the neutralization of superoxide. Whether short- or long-term, exposure to high glucose reportedly increases superoxide levels within human tissues including vascular smooth muscle cells.2,3 Considering these previous results, we conducted our study to evaluate the involvement of superoxide in the malfunction of cerebral microvessels induced by high glucose.1 It is also crucial to note that chronic hyperglycemia predisposes to exaggerated inflammatory response and leukocyte dysfunction corresponding with superoxide production induced by nicotinamide adenine dinucleotide phosphate oxidase.4 Therefore, it seems difficult to draw the conclusion that hydrogen peroxide solely contributes to all inflammatory processes induced by hyperglycemia and/or diabetes mellitus.
*Wakayama Medical University, Wakayama, Japan.
References
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