The Gaba Receptors

The Gaba Receptors, Third Edition, presents a critical appraisal of our current understanding of the molecular, behavioral, biochemical, clinical, and pharmacological properties of GABA receptors. Emphasis is placed on exploring cutting-edge findings on the structureal properties of receptor sites, mechanisms of receptor expression, chemical agents that differentiate receptor subtypes, and phenotypes displayed by GABA receptor null mice. Chapters in this updated and expanded edition examine such topics as GABA receptor subypes, trafficking postsynaptic GABA receptors, GABA receptor mutations associated with idiopathic generalized epilepsies and febrile seizures, and GABA receptors as a potential therapeutic target.

Jasper's Basic Mechanisms, Fourth Edition, is the newest most ambitious and now clinically relevant publishing project to build on the four-decade legacy of the Jasper's series. In keeping with the original goal of searching for "a better understanding of the epilepsies and rational methods of prevention and treatment.", the book represents an encyclopedic compendium neurobiological mechanisms of seizures, epileptogenesis, epilepsy genetics and comordid conditions. Of practical importance to the clinician, and new to this edition are disease mechanisms of genetic epilepsies and therapeutic approaches, ranging from novel antiepileptic drug targets to cell and gene therapies.

GABA is the principal inhibitory neurotransmitter in the CNS and acts via GABAA and GABAB receptors. Recently, a novel form of GABAA receptor-mediated inhibition, termed “tonic” inhibition, has been described. Whereas synaptic GABAA receptors underlie classical “phasic” GABAA receptor-mediated inhibition (inhibitory postsynaptic currents), tonic GABAA receptor-mediated inhibition results from the activation of extrasynaptic receptors by low concentrations of ambient GABA. Extrasynaptic GABAA receptors are composed of receptor subunits that convey biophysical properties ideally suited to the generation of persistent inhibition and are pharmacologically and functionally distinct from their synaptic counterparts. This book highlights ongoing work examining the properties of recombinant and native extrasynaptic GABAA receptors and their preferential targeting by endogenous and clinically relevant agents. In addition, it emphasizes the important role of extrasynaptic GABAA receptors in GABAergic inhibition throughout the CNS and identifies them as a major player in both physiological and pathophysiological processes.

An essential reference for psychiatrists, clinical psychologists, trainees, and specialist nurses, as well as primary care physicians/GPs with a special interest in mental health conditions and other healthcare professionals.

Highlighting the current developments and future directions in GABA research, the ambitious aim of this topical volume is to cover GABA from the molecular mechanisms of its transmission to new targets for pharmaceutical research. Distinguished scientists at the forefront of GABA research were invited to contribute reviews on glutamate decarboxylase and autoimmunity, molecular structure and functional regulation of GABA transporters, transmitter release and GABA receptor regulation, GABA receptor subtypes and functional regulation, and GABA receptor ligands and their therapeutic application. Describing the latest advances in what has become a rapidly-evolving field, this volume will prove immensely valuable to neuroscientists, pharmacologists, biochemists, and physiologists working in the field of GABA research.

Intoxication of humans and animals has become increasingly important in recent years as has contamination of the environment by a variety of chemicals. In order to develop effective means by which such intoxication and contamination can be properly handled, it is imperative to know how these environmental agents act in humans and animals. Despite studies conducted by various investigators, the mechanisms of action of these environmental agents have not been fully elucidated. Insecticides are by no means an exception in terms of the seriousness of the problem and of the urgency of the need for such information. In order to complete a picture of the effects of any particular insecticide, it is of utmost importance that its actions at various levels ranging from those of molecules to whole animals be analyzed and synthesized. To understand the toxicological action on animals or humans, it is not sufficient to know the action at each level only. The actions at various levels must be integrated to construct a picture of the toxic effect on the intact organism. However, in spite of the large body of information that has been accumulated during the past few decades, little or no attempt has been made to integrate experimental data obtained at the molecular, cellular, organ, and animal levels together in order to define the whole picture of insecticidal action.

The ubiquitous presence of glutamate and GABA receptors in the nervous system makes these receptor systems pivotal to our understanding of neurotransmission. Cloning of the molecular components of these receptor systems has provided insights to the selectivity of many drugs and detailed characterisation at the molecular level is emerging. Moreover, continuous development of novel and selective drugs has revealed detailed information on the mechanism of receptor activation and regulation. However, the rapid development of different aspects of glutamate and GABA receptor research makes it increasingly difficult to establish a general view of the field. Studies of the receptors are a multi-disciplinary task employing many specialised techniques. This book conveys recent discoveries in a framework of the basic concepts in the field of glutamate and GABA receptor research. Glutamate and GABA Receptors and Transporters: Structure, Function and Pharmacology is suitable for postgraduate students studying ligand gated channels but also beneficial for industrial and academic research scientists in both the glutamate and GABA field. Universities offering programs in neuroscience, molecular pharmacology or medicinal chemistry will find this a valuable reference.

Fundamental biochemical studies of basic brain metabolism focusing on the neuroactive amino acids glutamate and GABA combined with the seminal observation that one of the key enzymes, glutamine synthetase is localized in astroglial cells but not in neurons resulted in the formulation of the term “The Glutamate-Glutamine Cycle.” In this cycle glutamate released from neurons is taken up by surrounding astrocytes, amidated by the action of glutamine synthetase to glutamine which can be transferred back to the neurons. The conversion of glutamate to glutamine is like a stealth technology, hiding the glutamate molecule which would be highly toxic to neurons due to its excitotoxic action. This series of reactions require the concerted and precise interaction of a number of enzymes and plasma membrane transporters, and this volume provides in-depth descriptions of these processes. Obviously such a series of complicated reactions may well be prone to malfunction and therefore neurological diseases are likely to be associated with such malfunction of the enzymes and transporters involved in the cycle. These aspects are also discussed in several chapters of the book. A number of leading experts in neuroscience including intermediary metabolism, enzymology and transporter physiology have contributed to this book which provides comprehensive discussions of these different aspects of the functional importance of the glutamate-glutamine cycle coupling homeostasis of glutamatergic, excitatory neurotransmission to basic aspects of brain energy metabolism. This book will be of particular importance for students as well as professionals interested in these fundamental processes involved in brain function and dysfunction.