Cerebral Energy Metabolism And Metabolic Encephalopathy

In recent years, there has been rapid growth in knowledge pertaining to the nervous system. This has, in some measure, been due to the development and application of a number of techniques such as the 2-deoxyglucose method and microchemical methods for measuring metabolites and regional cerebral blood flow. Data from the application of these techniques are just beginning to be collected, and the next few years promise to bring many new and exciting findings. The study of energy metabolism in brain is particularly interesting due to the fact that although the brain has scant energy reserves (as compared with the liver), it has one of the highest metabolic rates in the body. Recent studies from several laboratories have shown a surprising divergence of re sponses to metabolic insult in different areas of brain. In this regard, the cer ebellum, for example, may have metabolic features which are uniqve from those of any other region. The high-energy phosphate compounds ATP and phos phocreatine, supplied by the oxidative metabolism of glucose, are necessary for normal cerebral functions such as the maintenance of membrane potentials, transmission of impulses, and synthetic processes. Interruption of substrate or "poisoning" of the system by a variety of means lead to a rapid change in cellular energetics, and ultimately cell death. From the clinical standpoint, an interesting feature of metabolic encephalopathy is that in many cases, early diagnosis and treatment may result in a rapid reversal of symptoms.

Metabolic Encephalopathy is meant to combine and correlate animal and human studies. It is hoped that increased awareness of the importance of early diagnosis and treatment of these disorders may result in a lowering of the incidence of structural changes and morbidity. These disorders hold a special fascination for both basic scientists and clinical investigators because they are accessible, treatable and there exists good animal models for study. Therefore, this book will pull together basic and clinical neuroscience issue in the treatment of specific metabolic encephalopathies.

Introductory Remarks.- Pathophysiology of Cerebral Ischemia.- The Interpretation of Ultrastructural Abnormalities in Cerebral Ischemia.- Short-Term Unilateral Ischemia in Gerbils: A Reevaluation.- Some New Aspects of the Pathochemistry of the Post-Ischemic Period.- Blood Flow, Oxygen, and Electrical Dynamics in Cerebral Ischemia.- Cytochemistry of Hippocampus Following Cerebral Ischemia.- Cerebral Water and Electrolyte Content Following Ischemia and Blood-Brain Barrier Disturbances.- Behavior of the Blood-Brain Barrier (BBB) in Cerebral Ischemia.- Reemphasis of the Role of 5-Hydroxytryptamine.

Brain Energy Metabolism addresses its challenging subject by presenting diverse technologies allowing for the investigation of brain energy metabolism on different levels of complexity. Model systems are discussed, starting from the reductionist approach like primary cell cultures which allow assessing of the properties and functions of a single brain cell type with many different types of analysis, however, at the expense of neglecting the interaction between cell types in the brain. On the other end, analysis in animals and humans in vivo is discussed, maintaining the full complexity of the tissue and the organism but making high demands on the methods of analysis. Written for the popular Neuromethods series, chapters include the kind of detailed description and key implementation advice that aims to support reproducible results in the lab. Meticulous and authoritative, Brain Energy Metabolism provides an ideal guide for researchers interested in brain energy metabolism with the hope of stimulating more research in this exciting and very important field.

The mammalian central nervous system depends almost - clusively on glucose as its major energy source. In addition, g- cose participates in other cerebral metabolic functions including the biosynthesis of neurotransmitters, such as acetylcholine and the amino acids. This volume of Neuromethods assembles currently available methods for the study of cerebral glucose and energy metabolism in vitro and in mm. In the first chapter, Lust et al. describe the various methods available for the appropriate fixation of brain tissue necessary for the study of cerebral energy metabolism. Different fixation methods are compared, and some concerns raised by the USDHHS in their guidelines for the care and use of laboratory animals are addressed. Specific fixation methods pertinent to the various measurements are also covered in other chapters. In vitro p- parations have, despite certain limitations, been found to be useful in the study of brain metabolism, since the biochemical envir- ment is amenable to rapid, controlled manipulation. The chapter by Lai and Clark describes methods for the isolation and characterization of metabolically active preparations of synaptic and non-synaptic mitochondria from brain, and studies of - zymes involved in glucose metabolism and glucose-derived neurotransmitter synthesis in these preparations are summarized. The chapter by Whittingham discusses methods of preparations of hippocampal slices for use in the study of energy metabolism. Measurement of glucose and of glycolytic and dicarboxylic acid cycle intermediates in neural tissues are described in the chapter by Bachelard.

Brain dysfunction is a major clinical problem in intensive care, with potentially debilitating long-term consequences for post-ICU patients of any age. The resulting extended length of stay in the ICU and post-discharge cognitive dysfunction are now recognized as major healthcare burdens. This comprehensive clinical text provides intensivists and neurologists with a practical review of the pathophysiology of brain dysfunction and a thorough account of the diagnostic and therapeutic options available. Initial sections review the epidemiology, outcomes, relevant behavioral neurology and biological mechanisms of brain dysfunction. Subsequent sections evaluate the available diagnostic options and preventative and therapeutic interventions, with a final section on clinical encephalopathy syndromes encountered in the ICU. Each chapter is rich in illustrations, with an executive summary and a helpful glossary of terms. Brain Disorders in Critical Illness is a seminal reference for all physicians and neuroscientists interested in the care and outcome of severely ill patients.