[Frontiers in Bioscience E2, 1275-1298, June 1, 2010]

Neuroprotections and mechanisms of inhalational anesthetics against brain ischemia

Qiong Yu1,2, Hailian Wang1,2, Jun Chen2,3, Yanqin Gao2, Weimin Liang1

1Department of Anesthesiology of Huashan Hospital, affiliated with Fudan University, Shanghai, China, 2State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, China, 3Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213

TABLE OF CONTENTS

1. Abstract
2. Introduction
3. Effects on ischemic brain
3.1. Experimental studies
3.1.1. Impact during brain ischemia
3.1.1.1. Neuroprotective effects during brain ischemia
3.1.1.1.1. Isoflurane
3.1.1.1.2. Sevoflurane
3.1.1.1.3. Desflurane
3.1.1.1.4. Xenon
3.1.1.2. No effect and detrimental effects during brain ischemia
3.1.2. Preconditioning effects
3.1.2.1. Neuroprotective effects of anesthetic preconditioning
3.1.2.1.1. Isoflurane
3.1.2.1.2. Sevoflurane
3.1.2.1.3. Desflurane
3.1.2.1.4. Xenon
3.1.2.2. No effect and detrimental effects of anesthetic preconditioning
3.1.3. Post-treatment effects
3.1.3.1. Neuroprotective effects of anesthetic post-treatment
3.1.3.2. No effect and detrimental effects of anesthetic post-treatment
3.2. Clinical studies
4. Mechanisms of impact on ischemic brain
4.1. Common mechanisms for pre- and peri-treatment
4.1.1. Electrophysiological and metabolic modulation
4.1.2. Reduciton of glutamate excitotoxicity
4.1.2.1. Glutamate release and uptake
4.1.2.2. NMDA and AMPA receptor antagonism
4.1.3. Intracellular calcium and calcium-dependent processes
4.1.4. Antioxidant mechanisms
4.1.5. Anti-apoptosis
4.2. Mechanisms for peri-treatment
4.2.1. Two-pore-domain potassium channels (K2P channels)
4.2.2. GABAA receptor potentiation
4.2.3. Catecholamine release
4.2.4. Neurogenesis
4.3. Mechanisms for preconditioning
4.3.1. ATP-sensitive potassium channels
4.3.2. Nitric oxide
4.3.3. Adenosine A1 receptor activation
4.4. Mechanisms for post-treatment
4.4.1. ATP-sensitive potassium channels
5. Summary and perspectives
6. Acknowledgements
7. References

1. ABSTRACT

The new generation of inhalational anesthetics has been widely used for general anesthesia in both clinical and experimental settings because of their safety, reliability and potency. A neuroprotective role has recently been revealed for some of these anesthetics, including the volatile gases isoflurane, sevoflurane, and desflurane, as well as the inert gas xenon. In vivo and in vitro studies have demonstrated that these gases were able to protect brain against ischemic injury, indicated by the decreases in infarct volumes and neuronal apoptosis. In this review, we will briefly introduce the properties of these gases, and discuss in detail their effects on brain ischemia, effective treatment regimens, and neuroprotective mechanisms. Perspectives are also discussed on future study and use of inhalational anesthetics.