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Dehydrogenase (DHO) is one of the most common types of enzyme that is crucial in oxidation reactions. This enzyme oxidizes its specific substrate by a redox reaction in which one or more hydrides (H−) are transferred to an electron acceptor. Apart from energetics and ATP formation, DHOs are associated with both catabolic and anabolic pathways linked to normal functioning and homeostasis. In this chapter, we will cover different aspects of the major DHOs that play a role in the regulation of brain and bloodbrain barrier (BBB) physiology starting from their role in bioenergetic metabolism. In born errors in metabolism (IEM) due to genetic deficiency in a single specific DHO have strong neurological implications. We will be covering some examples of such IEMs in this chapter. Furthermore, aging processes can impair the function or activity of DHOs. Recent studies show convincing evidence associating altered DHO activity with the pathogenesis and progression of several neurological disorders such as Alzheimer's and Parkinson's disease. Whether they are contributors to the etiology of the disease or symptomatic manifestation of these complex neurological disorders is still debatable; however, this link between DHOs and neurological disorders cannot be overlooked and will be further discussed in this chapter. We will also cover neuronal signaling, neurotransmitter release and degradation emphasizing localized region-specific expression of some brain DHOs in these processes. It is not possible to cover the detailed cerebral physiology and function in this chapter; however to summarize we will discuss the different types of DHOs in central nervous system (CNS) and BBB physiology, their key enzymatic action, their function in crucial metabolic pathways, and thus how their altered activity or expression can be linked to the underlying pathogenesis of various brain disorders.

© 2012 Naik et al., licensee InTech. This is an open access chapter distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2012 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
