Download or read book Modulation of Presynaptic Ion Channels written by Jeremy Ballard Bergsman and published by . This book was released on 2000 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Structure Function and Modulation of Neuronal Voltage Gated Ion Channels written by Valentin K. Gribkoff and published by John Wiley & Sons. This book was released on 2008-12-09 with total page 505 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses voltage-gated ion channels and their importance in drug discovery and development. The book includes reviews of the channel genome, the physiological bases of targeting ion channels in disease, the unique technologies developed for ion channel drug discovery, and the increasingly important role of ion channel screening in cardiac risk assessment. It provides an important reference for research scientists and drug discovery companies.
Download or read book Calcium and Ion Channel Modulation written by A. D. Grinnell and published by Springer. This book was released on 1988-06 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cellular neurobiology has been transformed in the past decade by new technologies and fundamental discoveries. One result is an enormous increase in our understanding of how ion channels function in nerve and muscle cells and a widening perspective on the role of ion channels in non-neuronal cell physiology and development. Patch clamp techniques now permit direct observation of the transitions between functional confor mations of individual ion channels in their native membrane. Recombinant DNA techniques are being used to determine the primary structure of ion channel proteins and to test hypotheses about channel conformations, sites of grating and modulation, and the basis of ion selectivity. At the same time, biochemical techniques have revealed intricate signalling systems in side cells, involving second messengers such as calcium, phospholipids and cyclic nucleotides, which interface with the external milieu through GTP binding proteins and regulate cell metabolism by altering protein phos phorylation. This panorama of second messenger systems has greatly increas ed our application for their potential role in regulating ion channel function. We now recognize that ion channels are much more complicated than we once thought, and more interesting. They are not simply isolated macro molecules in the membrane, gated directly by depolarization or trans mitter binding to open briefly at a fixed conductance and then close or inactivate. Instead, individual channels now appear to have many open and closed states that are regulated independently by voltage and transmitters.
Download or read book Modulation of Presynaptic Calcium Channels written by Gary Stephens and published by Springer Science & Business Media. This book was released on 2013-04-23 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book will bring together leading international experts to discuss recent advances in basic scientific knowledge regarding the regulation of presynaptic Ca2+ channels. Importantly, Ca2+ channels represent one of the most widely modulated proteins in the body, being the target of a range of effector pathways and drugs; this range will be fully represented here. A number of therapeutic drugs target the Ca2+ channel complex, including the anti-epileptic gabapentinoid and analgesic ziconotide drugs and the pharmaceutical industry is searching for Ca2+ channel blocking drugs, particularly in the pain, epilepsy, ataxia and migraine areas. Such potential future therapies will be discussed here. Scientific disciplines will focus on electrophysiological studies, but will extend to neuroscience, genetics and biochemical areas. The work described will represent advances at the cutting edge of current neuroscience research and is timely and highly appropriate for the Springer book series.
Download or read book Slow Synaptic Responses and Modulation written by K. Kuba and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt: Information flow as nerve impulses in neuronal circuits is regulated at synapses. The synapse is therefore a key element for information processing in the brain. Much attention has been given to fast synaptic transmission, which predominantly regulates impulse-to-impulse transmission. Slow synaptic transmission and modu lation, however, sometimes have been neglected in considering and attempting to understand brain function. Slow synaptic potentials and modulation occur with a considerable delay in response to the accumulation of synaptic and modulatory inputs. In these contexts, they are plastic in nature and play important roles in information processing in the brain. A symposium titled "Slow Synaptic Responses and Modulation" was held as the satellite symposium to the 75th Annual Meeting of the Physiological Society of Japan on March 30-31, 1998, in Kanazawa. The theme was selected not only for the reason mentioned above, but also because of the considerable involvement of many Japanese scholars in establishing the basic issues. Following the dawn of synaptic physiological research, as Sir John Eccles, Sir Bernard Katz, and Professor Stephen Kuffler carried out pioneer work, Professor Kyozou Koketsu and Professor Benjamin Libet, the students of Sir John Eccles, and their colleagues established the concept of slow synaptic responses and modulation by studying vertebrate sympathetic ganglia. Since then, the concept has been ex panded with detailed investigations of both peripheral and central synapses at the levels of single ion channels, intracellular Ca"+ dynamics, intracellular transduc tion mechanisms, and genes.
Download or read book Molecular Biology of the Cell written by and published by . This book was released on 2002 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mechanisms of Presynaptic CaV2 2 N type Modulation written by Allen Chan and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Neurotransmitter release at presynaptic terminals is a complex process involving calcium ion influx through voltage-gated calcium channels (CaV). In addition to their role as entry points through which calcium influx may occur, CaV are now understood to be fundamental components of a common release-site complex that is highly adapted for modulation. Consistent with this model, I investigated mechanisms of modulating a presynaptic calcium channel, CaV2.2, via a heterotrimeric G-protein pathway. Using the patch-clamp technique, I demonstrated in chick dorsal root ganglion (DRG) neurons that the slow kinetics of G-protein inhibition of CaV2.2 via GTPgammaS were limited by the rate of GDP dissociation from the G-protein nucleotide binding site. In addition, I investigated the role of G-protein regulation of CaV2.2 currents evoked by action potential-like stimuli. Here, I characterized an inhibited current that was advanced in time with respect to uninhibited controls. These currents exhibited a shorter latency to current activation and faster deactivation. These findings may have important physiological ramifications on signal transduction and timing. In addition to G-protein regulation, presynaptic CaV2.2 have been demonstrated to exhibit a resistance to voltage-dependent inactivation (VDI), a property thought to be important in determining channel availability and synaptic excitability. I demonstrated a role for dynamic palmitoylation in conferring resistance to VDI in presynaptic terminals of the chick ciliary ganglion. Using tunicamycin, an inhibitor of palmitoylation, I induced a hyperpolarizing shift in the steady-state-inactivation (SSI) profile of presynaptic CaV2.2. Finally, I examined the role of a CaV interacting protein, Munc18, as a potential regulator of CaV. I probed for alterations in CaV2.2 function in DRG neurons that had been transfected with Munc18 or Munc18 siRNA. Despite the intimate interaction between Munc18 and CaV2.2, no major effects on the fundamental characteristics of CaV2.2 function were observed. However, a hyperpolarizing shift in the inactivation profile of CaV2.2 was determined in DRG neurons in which Munc18 was knocked down. It is not clear if this was a direct consequence of Munc18 perturbation.
Download or read book Neurotransmitter Release written by Hugo J. Bellen and published by Oxford University Press, USA. This book was released on 1999 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides the reader with background information on neurotransmitter release. Emphasis is placed on the rationale by which proteins are assigned specific functions rather than just providing facts about function.
Download or read book Pumps Transporters and Ion Channels written by Francisco Sepulveda and published by Springer Science & Business Media. This book was released on 2006-03-30 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a compilation of articles based on some of the talks given at the Centro de Estudios Cientificos (CECS) in Valdivia during the course of a celebration to th mark the 60 birthdays of Ramon Latorre and Enrico Stefani. Ramon Latorre is one of the most outstanding figures in channel Biophysics today. The first surprise is that he trained as a Biochemist! He soon, however, became a biophysicist through his work with Guayo (Eduardo) Rojas who guided him during his Ph. D thesis in the Laboratorio de Fisiologia Celular in Montemar. His work at N.I.H with Gerald Eherenstein and Harold Lecar constitutes one of the milestones of single ion channel Biophysics. This classical work, done in planar bilayers, set the basis for understanding voltage-dependent conductances with single channel studies and predates, by many years, later studies using patch clamping techniques. Ramon was one of the firsts to find and recognize the importance of calci- activated potassium channels and to begin a detailed study of channel properties. He pioneered the ideas of voltage and calcium modulation of the open probability and he added detailed studies of gating and its modulation by other ions. Ramon is also interested in permeation and selectivity and he produced classical studies on the number of water molecules in the channel and sites occupied by barium. Results and concepts that have recently taken front page as the structure of KcSa has been described.
Download or read book Mechanisms of Presynaptic Ca subscript v2 2 N type Modulation written by Allen W. Chan and published by . This book was released on 2008 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt: Neurotransmitter release at presynaptic terminals is a complex process involving calcium ion influx through voltage-gated calcium channels (Ca V). In addition to their role as entry points through which calcium influx may occur, CaV are now understood to be fundamental components of a common release-site complex that is highly adapted for modulation.In addition to G-protein regulation, presynaptic CaV2.2 have been demonstrated to exhibit a resistance to voltage-dependent inactivation (VDI), a property thought to be important in determining channel availability and synaptic excitability. I demonstrated a role for dynamic palmitoylation in conferring resistance to VDI in presynaptic terminals of the chick ciliary ganglion. Using tunicamycin, an inhibitor of palmitoylation, I induced a hyperpolarizing shift in the steady-state-inactivation (SSI) profile of presynaptic Ca V2.2.Finally, I examined the role of a CaV interacting protein, Munc18, as a potential regulator of CaV. I probed for alterations in CaV2.2 function in DRG neurons that had been transfected with Munc18 or Munc18 siRNA. Despite the intimate interaction between Munc18 and CaV2.2, no major effects on the fundamental characteristics of CaV2.2 function were observed. However, a hyperpolarizing shift in the inactivation profile of CaV2.2 was determined in DRG neurons in which Munc18 was knocked down. It is not clear if this was a direct consequence of Munc18 perturbation.Consistent with this model, I investigated mechanisms of modulating a presynaptic calcium channel, CaV2.2, via a heterotrimeric G-protein pathway. Using the patch-clamp technique, I demonstrated in chick dorsal root ganglion (DRG) neurons that the slow kinetics of G-protein inhibition of Ca V2.2 via GTPgammaS were limited by the rate of GDP dissociation from the G-protein nucleotide binding site. In addition, I investigated the role of G-protein regulation of CaV2.2 currents evoked by action potential-like stimuli. Here, I characterized an inhibited current that was advanced in time with respect to uninhibited controls. These currents exhibited a shorter latency to current activation and faster deactivation. These findings may have important physiological ramifications on signal transduction and timing.
Download or read book Neuromodulation written by Irwin B. Levitan and published by . This book was released on 1987 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Traditional neuroscience texts have stressed the output of neurons, how they turn postsynaptic targets on or off, cause muscles to twitch or convert photons into electrical pulses. Neuromodulation alters that emphasis to examine how the responses of nerve cells can be modified. Because a neuron's performance can be modulated, brains of all animals exhibit the amazing capacity to learn. Presenting the best-studied examples, Kaczmarek and Levitan provide the first detailed review of those potassium and calcium channels whose functions are modulated through receptor-mediated second messenger mechanisms and that are thought to underlie many important kinds of neuronal plasticity. This book, which covers up-to-date biophysical work in both vertebrate and invertebrate neurons, will be greatly appreciated by the readership the authors wish to reach: neurophysiological biochemists and biochemical neurophysiologists interested in understanding how behavior results from the action of nerve cells."--James H. Schwartz, M.D., Ph.D., Columbia University College of Physicians and Surgeons
Download or read book Fine tuning Synaptic Plasticity by Modulation of Presynaptic Cav2 1 Channels with Ca2 Sensor Proteins written by Karina Leal and published by . This book was released on 2012 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt: Short-term plasticity of synaptic transmission is recognized as an important component of information processing in neuronal networks. Repetitive firing in neurons either leads to an increase, or to a decrease in synaptic transmission, processes referred to as facilitation and depression. This short-term plasticity behavior of synaptic transmission is specifically regulated at each given synaptic connection. P/Q-type and N-type Ca2+ currents through Cav2.1 and Cav2.2 channels, respectively, are responsible for the Ca2+ entry that initiates neurotransmitter release at most conventional synapses. However, it remains not well understood to what extent regulation of Cav2.1 channels play a role in short-term plasticity. Recent work has shown Ca2+-dependent regulation of Cav2.1 channels to be mediated by calmodulin (CaM) and neuronal Ca sensors (CaS), which include calcium binding protein 1 (CaBP1) and visinin-like protein 2 (VILIP-2). Mutations of the CaS binding sites in the carboxyl terminal of Cav2.1 affect short-term synaptic plasticity. Although it is clear that CaS-dependent regulation of Cav2.1 channels induces synaptic plasticity, it remains unknown which CaS proteins are responsible for these changes. Candidate proteins include, CaM, CaBP1, and VILIP-2, which show differential modulation of Cav2.1 channels in heterologous expression systems; yet, their role in synaptic transmission has not been studied. Here, we show that activity-dependent modulation of presynaptic CaV2.1 channels by CaBP1 and VILIP-2 has opposing effects on short-term synaptic plasticity in superior cervical ganglion (SCG) neurons. Expression of CaBP1, which blocks Ca2+-dependent facilitation of P/Q-type Ca2+ current, markedly reduced facilitation of synaptic transmission. VILIP-2, which blocks Ca2+-dependent inactivation of P/Q-type Ca2+ current, reduced synaptic depression and increased facilitation under conditions of high release probability. These results demonstrate that activity-dependent regulation of presynaptic CaV2.1 channels by differentially expressed CaS proteins can fine-tune synaptic responses to trains of action potentials and thereby contribute to the diversity of short-term synaptic plasticity.
Download or read book Pharmacology of Neurotransmitter Release written by Thomas C. Südhof and published by Springer Science & Business Media. This book was released on 2007-12-07 with total page 582 pages. Available in PDF, EPUB and Kindle. Book excerpt: It has been known for half a century that neurotransmitters are released in preformed quanta, that the quanta represent transmitter-storing vesicles, and that release occurs by exocytosis. The focus of this book is twofold. In the first part, the molecular events of exocytosis are analysed. In the second part of the book, the presynaptic receptors for endogenous chemical signals are presented that make neurotransmitter release a highly regulated process.
Download or read book Voltage sensitive Ion Channels written by Giovanni Biggio and published by Liviana Scolastica. This book was released on 1988 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modulation of Presynaptic Function The Role of Protein Ubiquitination and the Effects of Environmental Toxins written by Katherine Myers and published by . This book was released on 2016 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: The nervous system rapidly integrates sensory modalities with higher order cognition to generate a seamless and appropriate output in the form of motor activity, behavior and cognitive functions. In order to do so, modification within neural circuits, individual cells and unique synapses is constantly occurring. In this dissertation, I focused on the problem of rapid modifications at pre-synaptic sites, and how those modifications generate information transfer in the form of synaptic vesicle release. In the first section of this dissertation, I examined the role of synaptic protein ubiquitination in modulating pre-synaptic release properties. In the second and third sections of the dissertation, I characterized the effects of agricultural pesticides, in particular ziram, on synaptic transmission. Electrophysiological recordings of mammalian neurons acutely exposed to inhibitors of ubiquitination indicate that disrupting the pathway at various points in the ubiquitin cycle leads to enhanced spontaneous release in a matter of minutes. Imaging with fluorescent reporters of exo and endocytosis further suggest a role for synaptic protein ubiquitination in modulating evoked release within the same time frame; inhibitors rapidly reduced the amount of stimulated exocytosis, possibly through or in parallel to disruption of endocytosis and synaptic vesicle recycling. Similar techniques were employed to examine the effects of ziram and other pesticides which are linked to an increased risk of Parkinson's disease (PD) at mammalian and invertebrate synapses. Drosophila melanogaster larvae expressing either fluorescent sensors of exo and endocytosis, calcium, or voltage were used to measure changes in release at glutamatergic and aminergic neurons of the neuromuscular junction (NMJ) exposed to ziram. Combined, data from the NMJ and mammalian neurons demonstrated that ziram and other dithiocarbamate chemicals enhance spontaneous synaptic vesicle fusion and lead to spontaneous neural activity in aminergic neurons. Ziram leads to a depolarization of membranes, and differences in the outcome following exposure at different neurons may be related to pre-synaptic ion channel composition. These data offer insight into the dynamic modulation of release properties via ubiquitination, and offer insight into pre-synaptic changes in excitability that may occur in the onset and during the development of PD linked to environmental toxins.
Download or read book PH and Brain Function written by Kai Kaila and published by John Wiley & Sons. This book was released on 1998-09-15 with total page 694 pages. Available in PDF, EPUB and Kindle. Book excerpt: "PH and Brain Function offers thorough coverage of this increasingly important area of research, beginning with the fundamental concepts, which include methodological and theoretical issues such as the measurement of pH and the concept of pH in neurobiology. It explores aspects of regulation and modulation of intracellular pH in brain cells, surveys the changes in pH that occur with neural activity and how these changes affect neural activity, and discusses the role of pH in the pathophysiology of neurological diseases." "pH and Brain Function is an important resource for researchers in all areas of neuroscience as well as cell biology and physiology." --Book Jacket.
Download or read book Presynaptic Receptors and Neuronal Transporters written by S.Z. Langer and published by Elsevier. This book was released on 2013-10-22 with total page 373 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in the Biosciences, Volume 82: Presynaptic Receptors and Neuronal Transporters documents the proceedings of the Official Satellite Symposium to the IUPHAR 1990 Congress held in Rouen, France on June 26-29, 1990. The first part of this book deals with the extensive and still increasing list of presynaptic release-modulating auto and heteroreceptors, emphasizing the various subtypes of presynaptic receptors that are characterized by functional studies, both in vitro and in vivo, using a number of experimental approaches. The next chapters are devoted to the molecular pharmacology of presynaptic receptors, of which can interfere with G proteins and modify the activity of adenylate cyclase, guanylate cyclase, or protein kinase C. The purification and molecular biology of transporter systems, including cloning and sequencing of the neuronal sodium-ion coupled GABA transporter are also discussed. This compilation concludes with insights on the function of presynaptic receptors and neuronal transporters both in the periphery and in the CNS, as well as their ubiquitous locations and physiological roles. This publication is a good reference for students and individuals researching on the presynaptic autoreceptors and neurotransmitters.
