The metabolomic profile during isoflurane anesthesia differs from propofol anesthesia in the live rodent brain

Department of Anesthesiology, Health Sciences Center, Stony Brook University, Stony Brook, New York 11794, USA.
Journal of cerebral blood flow and metabolism: official journal of the International Society of Cerebral Blood Flow and Metabolism (Impact Factor: 5.41). 01/2011; 31(6):1432-42. DOI: 10.1038/jcbfm.2011.1
Source: PubMed


Development of noninvasive techniques to discover new biomarkers in the live brain is important to further understand the underlying metabolic pathways of significance for processes such as anesthesia-induced apoptosis and cognitive dysfunction observed in the undeveloped brain. We used in vivo proton magnetic resonance spectroscopy and two different signal processing approaches to test the hypothesis that volatile (isoflurane) and intravenous (propofol) anesthetics at equipotent doses produce distinct metabolomic profiles in the hippocampus and parietal cortex of the live rodent. For both brain regions, prolonged isoflurane anesthesia was characterized by higher levels of lactate (Lac) and glutamate compared with long-lasting propofol. In contrast, propofol anesthesia was characterized by very low concentrations of Lac ([lac]) as well as glucose. Quantitative analysis revealed that the [lac] was fivefold higher with isoflurane compared with propofol anesthesia and independent of [lac] in blood. The metabolomic profiling further demonstrated that for both brain regions, Lac was the most important metabolite for the observed differences, suggesting activation of distinct metabolic pathways that may impact mechanisms of action, background cellular functions, and possible agent-specific neurotoxicity.

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Available from: Rany Makaryus, Aug 14, 2014
    • "At the protein level, sevoflurane changes the expression of various proteins involved in intercellular communication and metabolism (Kalenka et al., 2007). In the brain, isoflurane exposure results in higher lactate and glutamate levels in the hippocampus and parietal cortex regions (Makaryus et al., 2011). Isoflurane exposure can also decrease long-term potentiation in the lateral nuclei of the amygdala, affecting brain plasticity and brain tissue sample quality (Kulisch et al., 2011). "
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