Cellular Neurophysiology Lecture
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
2 Lez Concept of Synapses
Synapse • Gaps Between Neurons A synapse is a specialised junction between 2 neurones where the nerve impulse is passed from one neuron to another Santiago Ramón Camillo Golgi y Cajal The Nobel Prize in Physiology or Medicine 1906 was awarded jointly to Camillo Golgi and Santiago Ramón y Cajal "in recognition of their work on the structure of the nervous system Reticular vs Neuronal Doctrine The 1930 s and 1940s was a time of controversy between proponents of chemical and electrical theories of synaptic transmission. Henry Dale was a pharmacologist and a principal advocate of chemical transmission. His most prominent adversary was the neurophysiologist, JohnEccles. Otto Loewi, MD Nobel Laureate (1936) Types of Synapses • Synapses are divided into 2 groups based on zones of apposition: • Electrical • Chemical – Fast Chemical – Modulating (slow) Chemical Gap-junction Channels • Connect communicating cells at an electrical synapse • Consist of a pair of cylinders (connexons) – one in presynaptic cell, one in post – each cylinder made of 6 protein subunits – cylinders meet in the gap between the two cell membranes • Gap junctions serve to synchronize the activity of a set of neurons Electrical synapse Electrical Synapses • Common in invertebrate neurons involved with important reflex circuits. • Common in adult mammalian neurons, and in many other body tissues such as heart muscle cells. • Current generated by the action potential in pre-synaptic neuron flows through the gap junction channel into the next neuron • Send simple depolarizing -
The Hippocampus Marion Wright* Et Al
WikiJournal of Medicine, 2017, 4(1):3 doi: 10.15347/wjm/2017.003 Encyclopedic Review Article The Hippocampus Marion Wright* et al. Abstract The hippocampus (named after its resemblance to the seahorse, from the Greek ἱππόκαμπος, "seahorse" from ἵππος hippos, "horse" and κάμπος kampos, "sea monster") is a major component of the brains of humans and other vertebrates. Humans and other mammals have two hippocampi, one in each side of the brain. It belongs to the limbic system and plays important roles in the consolidation of information from short-term memory to long-term memory and spatial memory that enables navigation. The hippocampus is located under the cerebral cortex; (allocortical)[1][2][3] and in primates it is located in the medial temporal lobe, underneath the cortical surface. It con- tains two main interlocking parts: the hippocampus proper (also called Ammon's horn)[4] and the dentate gyrus. In Alzheimer's disease (and other forms of dementia), the hippocampus is one of the first regions of the brain to suffer damage; short-term memory loss and disorientation are included among the early symptoms. Damage to the hippocampus can also result from oxygen starvation (hypoxia), encephalitis, or medial temporal lobe epilepsy. People with extensive, bilateral hippocampal damage may experience anterograde amnesia (the inability to form and retain new memories). In rodents as model organisms, the hippocampus has been studied extensively as part of a brain system responsi- ble for spatial memory and navigation. Many neurons in the rat and mouse hippocampus respond as place cells: that is, they fire bursts of action potentials when the animal passes through a specific part of its environment. -
Sir Charles Sherrington'sthe Integrative Action of the Nervous System: a Centenary Appreciation
doi:10.1093/brain/awm022 Brain (2007), 130, 887^894 OCCASIONAL PAPER Sir Charles Sherrington’sThe integrative action of the nervous system: a centenary appreciation Robert E. Burke Formerly Chief of the Laboratory of Neural Control, National Institute of Neurological Disorders, National Institutes of Health, Bethesda, MD, USA Present address: P.O. Box 1722, El Prado, NM 87529,USA E-mail: [email protected] In 1906 Sir Charles Sherrington published The Integrative Action of the Nervous System, which was a collection of ten lectures delivered two years before at Yale University in the United States. In this monograph Sherrington summarized two decades of painstaking experimental observations and his incisive interpretation of them. It settled the then-current debate between the ‘‘Reticular Theory’’ versus ‘‘Neuron Doctrine’’ ideas about the fundamental nature of the nervous system in mammals in favor of the latter, and it changed forever the way in which subsequent generations have viewed the organization of the central nervous system. Sherrington’s magnum opus contains basic concepts and even terminology that are now second nature to every student of the subject. This brief article reviews the historical context in which the book was written, summarizes its content, and considers its impact on Neurology and Neuroscience. Keywords: Neuron Doctrine; spinal reflexes; reflex coordination; control of movement; nervous system organization Introduction The first decade of the 20th century saw two momentous The Silliman lectures events for science. The year 1905 was Albert Einstein’s Sherrington’s 1906 monograph, published simultaneously in ‘miraculous year’ during which three of his most celebrated London, New Haven and New York, was based on a series papers in theoretical physics appeared. -
Cajal, Golgi, Nansen, Schäfer and the Neuron Doctrine
Full text provided by www.sciencedirect.com Feature Endeavour Vol. 37 No. 4 Cajal, Golgi, Nansen, Scha¨ fer and the Neuron Doctrine 1, Ortwin Bock * 1 Park Road, Rosebank, 7700 Cape Town, South Africa The Nobel Prize for Physiology or Medicine of 1906 was interconnected with each other as well as connected with shared by the Italian Camillo Golgi and the Spaniard the radial bundle, whereby a coarsely meshed network of Santiago Ramo´ n y Cajal for their contributions to the medullated fibres is produced which can already be seen at 2 knowledge of the micro-anatomy of the central nervous 60 times magnification’. Gerlach’s work on vertebrates system. In his Nobel Lecture, Golgi defended the going- helped to consolidate the evolving Reticular Theory which out-of-favour Reticular Theory, which stated that the postulated that all the cells of the central nervous system nerve cells – or neurons – are fused together to form a were joined together like an electricity distribution net- diffuse network. Reticularists like Golgi insisted that the work. Gerlach was one of the most influential anatomists of axons physically join one nerve cell to another. In con- his day and the author of many books, not least the 1848 trast, Cajal in his lecture said that his own studies Handbuch der Allgemeinen und Speciellen Gewebelehre des confirmed the observations of others that the neurons Menschlichen Ko¨rpers: fu¨ r Aerzte und Studirende. For are independent of one another, a fact which is the twenty years he lent his considerable credibility to the anatomical basis of the now-accepted Neuron Doctrine Reticular Theory. -
The Excitable Cell. Resting Membrane Potential and Action Potential (1&2)
The excitable cell. Resting Membrane Potential and Action Potential (1&2) Dr Sergey Kasparov School of Medical Sciences, Room E9 THIS TOPIC IS ALSO COVERED IN TUTORIALS! Teaching home page: http://www.bristol.ac.uk/phys-pharm/media/teaching/ Why do we call these cells “excitable”? Real action potentials.avi The key point: Bioelectricity is generated by the ions moving across cellular membranes Concentration of selected solutes in intracellular fluid and extracellular fluid in millimols mM 160 140 120 100 Insi de the cell 80 60 In extracellular fluid 40 20 0 1 The Na+/K+ pump outside inside [[mMmM]] + + [[mMmM]] + + + + + + + Na 145 + + 15 + K 4 + + 140 ATPATP ••isis an active ion transporter (ATP‐dependent) ••isis responsible for creating and upholding Na+ and K+ concentration gradients ••isis electrogenic – pumps 3 Na+ versus 2 K+ ions Reminder: Movement of ions is affected by concentration gradient and the electrical field Chemical driving force _ _ + + _ + + Electrical driving force _ + + _ + + + _+ _ + _ + + + + _ + _ + _ + + _ Net flux + + + + _ + _ + + V REMINDER: Diffusion through Ion Channels A leak channel A gated channel Both leak and gated channels allow movement of molecules (mainly inorganic ions) down the electrochemical gradient. So, if the gradient reverses, the ions will flow in the opposite direction. 1. The channels are aqueous pores through the membrane. 2. The channels are usually quite selective, for example some only pass Na+, others K+, still others – Cl- 3. Gated channels may be opened or closed by various factors -
Balcomk41251.Pdf (558.9Kb)
Copyright by Karen Suzanne Balcom 2005 The Dissertation Committee for Karen Suzanne Balcom Certifies that this is the approved version of the following dissertation: Discovery and Information Use Patterns of Nobel Laureates in Physiology or Medicine Committee: E. Glynn Harmon, Supervisor Julie Hallmark Billie Grace Herring James D. Legler Brooke E. Sheldon Discovery and Information Use Patterns of Nobel Laureates in Physiology or Medicine by Karen Suzanne Balcom, B.A., M.L.S. Dissertation Presented to the Faculty of the Graduate School of The University of Texas at Austin in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy The University of Texas at Austin August, 2005 Dedication I dedicate this dissertation to my first teachers: my father, George Sheldon Balcom, who passed away before this task was begun, and to my mother, Marian Dyer Balcom, who passed away before it was completed. I also dedicate it to my dissertation committee members: Drs. Billie Grace Herring, Brooke Sheldon, Julie Hallmark and to my supervisor, Dr. Glynn Harmon. They were all teachers, mentors, and friends who lifted me up when I was down. Acknowledgements I would first like to thank my committee: Julie Hallmark, Billie Grace Herring, Jim Legler, M.D., Brooke E. Sheldon, and Glynn Harmon for their encouragement, patience and support during the nine years that this investigation was a work in progress. I could not have had a better committee. They are my enduring friends and I hope I prove worthy of the faith they have always showed in me. I am grateful to Dr. -
E Neurobiology of Learning and Memory – As Related in the Memoirs of Eric R
www.surgicalneurologyint.com Surgical Neurology International Editor-in-Chief: Nancy E. Epstein, MD, Clinical Professor of Neurological Surgery, School of Medicine, State U. of NY at Stony Brook. SNI: Socioeconomics, Politics, and Medicine Editor James A Ausman, MD, PhD University of California at Los Angeles, Los Angeles, CA, USA Open Access Book Review e neurobiology of learning and memory – as related in the memoirs of Eric R. Kandel Miguel A. Faria Clinical Professor of Surgery (Neurosurgery, ret.) and Adjunct Professor of Medical History (ret.), Mercer University School of Medicine, United States. E-mail: *Miguel A. Faria - [email protected] Author : Eric R. Kandel Published by : W.W. Norton & Co., New York, NY, USA Price : $19.95 ISBN-13 : 978-0393329377 ISBN-10 : 9780393329377 Year : 2006 *Corresponding author: Miguel A. Faria, MD Clinical Professor of Surgery (Neurosurgery, ret.) and Adjunct Professor of Medical History (ret.), Mercer University School of Medicine, United States. [email protected] is magnificent tome by Eric R. Kandel, M.D., a psychoanalyst and neuroscience researcher, Received : 22 July 2020 is both a delightful autobiography and a scrupulously detailed history of the neurobiology of Accepted : 22 July 2020 learning and memory, a relatively new area of neuroscience that Kandel refers to as a “new [7] Published : 15 August 2020 science of mind.” His own fundamental work in this area made him a recipient of a Nobel Prize in Physiology or Medicine in 2000, which he shared with two other distinguished investigators, DOI Drs. Arvid Carlsson (for elucidating the effects of dopamine in Parkinson’s disease) and Paul 10.25259/SNI_458_2020 Greengard (for the discovery of signal transduction in neurons). -
Vesicular Transport in Cells – from Analysis to Biogenesis
Powered by Website address: https://www.gesundheitsindustrie- bw.de/en/article/news/vesicular-transport-in-cells-from- analysis-to-biogenesis Vesicular transport in cells – from analysis to biogenesis COPI vesicles, one of the three major types of intracellular transport vesicles, are an excellent example of how the molecular analysis of individual vesicle components can lead to an understanding of the biogenesis and transport mechanisms of membrane vesicles as a whole. The research carried out by Dr. Felix T. Wieland’s team at the University of Heidelberg has made a decisive contribution to such detailed insights. Eukaryotic cells are characterised by complex membrane systems that separate different metabolic compartments from each other at the same time as transporting metabolic products and messenger substances to specific destinations inside the cell and into the extracellular space. The transport is mediated by vesicles that detach from the folded and branched cisternae of intracellular membranes. They either then fuse with intracellular membranes again or with the plasma membrane where the contents of the vesicles, secretory proteins for example, are discharged to the outside of the cell. This process is referred to as exocytosis. The opposite process is known as endocytosis, in which cells take up molecules from the exterior by enveloping them in their cell membrane before releasing them inside the cell. Camillo Golgi (1843-1926). © Universitá degli studi di Pavia The Golgi apparatus, named after the Italian physiologist Camillo Golgi who discovered a method to 1 stain nervous tissue with silver, which led to his discovery in 1898 of the "apparato reticulare interno" in the hippocampal neurons, is integral in modifying and packaging macromolecules for exocytosis or use within the cell (endocytosis). -
Synaptic Conductance Models
Synaptic Conductance Models BENG/BGGN 260 Neurodynamics University of California, San Diego Week 4 BENG/BGGN 260 Neurodynamics (UCSD) Synaptic Conductance Models Week 4 1 / 14 Reading Material C. Koch, Biophysics of Computation, Oxford Univ. Press, 1999, Ch. 1, pp. 14-23 and 85-115. B. Hille, Ion Channels of Excitable Membranes, Sinauer, 2001, Ch. 6, pp. 169-100. A. Destexhe, Z.F. Mainen and T.J. Sejnowski, \Synthesis of Models for Excitable Membranes, Synaptic Transmission and Neuromodulation Using a Common Kinetic Formalism", J. Comp. Neuroscience, vol. 1, pp. 195-230, 1994. P. Dayan and L. Abbott, Theoretical Neuroscience, MIT Press, 2001, Ch. 5.8, pp. 177-178. BENG/BGGN 260 Neurodynamics (UCSD) Synaptic Conductance Models Week 4 2 / 14 Synaptic Transmission neurotransmitter vesicle receptor axon dendrite action postsynaptic potential t t current tpre presynaptic synaptic postsynaptic terminal cleft terminal Presynaptic action potential triggers release of neurotransmitter (through Ca2+) Postsynaptic binding of neurotransmitter at receptor induces opening of a channel leading to a postsynaptic current I Excitatory (AMPA, NMDA, ...) t EPSC ! EPSP I Inhibitory (GABAA, ...) t IPSC ! IPSP tpre BENG/BGGN 260 Neurodynamics (UCSD) Synaptic Conductance Models Week 4 3 / 14 Synapses are Stochastic Fig. 4.4 Postsynaptic Amplitude Is Highly Variable Fluctuations in the amplitude of EPSPs observed in a pyramidal cell by evoking an action potential in a nearby pyramidal cell. Both pairs of neurons are located in layer 2/3 of brain slices taken from rat visual cortex. (A) Four individual sweeps from the same synaptic connection. The EPSP amplitude over the entire population of cell pairs is 0:55 ± 0:49 mV. -
Endogenous Serotonin Excites Striatal Cholinergic Interneurons Via The
Neuropsychopharmacology (2007) 32, 1840–1854 & 2007 Nature Publishing Group All rights reserved 0893-133X/07 $30.00 www.neuropsychopharmacology.org Endogenous Serotonin Excites Striatal Cholinergic Interneurons via the Activation of 5-HT 2C, 5-HT6, and 5-HT7 Serotonin Receptors: Implications for Extrapyramidal Side Effects of Serotonin Reuptake Inhibitors 1 1,2 3 1 3 2 Paola Bonsi , Dario Cuomo , Jun Ding , Giuseppe Sciamanna , Sasha Ulrich , Anne Tscherter , 1,2 3 ,1,2 Giorgio Bernardi , D James Surmeier and Antonio Pisani* 1 2 Fondazione Santa Lucia I.R.C.C.S., European Brain Research Institute, Rome, Italy; Clinica Neurologica, Dipartimento di Neuroscienze, 3 Universita` di Roma ‘Tor Vergata’, Rome, Italy; Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA The striatum is richly innervated by serotonergic afferents from the raphe nucleus. We explored the effects of this input on striatal cholinergic interneurons from rat brain slices, by means of both conventional intracellular and whole-cell patch-clamp recordings. Bath- applied serotonin (5-HT, 3–300 mM), induced a dose-dependent membrane depolarization and increased the rate of spiking. This effect was mimicked by the 5-HT reuptake blockers citalopram and fluvoxamine. In voltage-clamped neurons, 5-HT induced an inward current, + + whose reversal potential was close to the K equilibrium potential. Accordingly, the involvement of K channels was confirmed either by + + increasing extracellular K concentration and by blockade of K channels with barium. Single-cell reverse transcriptase-polymerase chain reaction (RT-PCR) profiling demonstrated the presence of 5-HT2C, 5-HT6, and 5-HT7 receptor mRNAs in identified cholinergic interneurons. -
Syllabus for Introduction to Neuroscience (Honors-‐ NROSCI 1003)
Syllabus for Introduction to Neuroscience (Honors- NROSCI 1003) This HONORS course provides an introduction to the structure and function of the nervous system. The course is comprised of four sections: 1) The molecular and cellular physiology of neurons, 2) Sensory systems, 3) Somatic and Visceral motor systems, 4) Complex Brain Functions (Emotions, Memory, Language, Disease). This course will also integrate weekly, in depth discussions of journal articles that correspond to Nobel Prize winning neuroscience research. Time: Tuesday, Thursday & Friday 11:00-12:15 pm Location: Crawford 241 Course Textbook: Neuroscience 5th Edition, 2012, Editors: Purves et al. Required: Scientific calculator with logarithmic function (NO graphing, phone or programmable calculators will be allowed for exams) Instructor: Dr. Oswald, [email protected] Office: A458 Langley, Mailbox: A210 Langley Office Hours: Thursday 10:00 am -11:00 am, or by appointment Teaching Assistants UTA: Samantha Golden, Julia Strother, Wyatt Laskey Weekly Assignments: Each Monday a reading assignment and three associated questions will be posted on CourseWeb. Answers are due before class on the day the reading assignment is discussed. Assignments are worth 10% of final grade. Weekly Quizzes: Quizzes will be every Tuesday in the first 15 min of class (No quiz during exam weeks). Each quiz will be worth 5 points. The quizzes will be on the material from lectures of the preceding week. Quizzes are optional but may be applied toward grade (see grading below). Grading: Grades will be determined based on the four in-class exams during the semester (90% of grade, see weighting below). There are no make-up exams. -
The Current-/Voltage-Clamp
SimNeuron Tutorial 1 SimNeuron Current-and Voltage-Clamp Experiments in Virtual Laboratories Tutorial Contents: 1. Lab Design 2. Basic CURRENT-CLAMP Experiments 2.1 Action Potential, Conductances and Currents. 2.2 Passive Responses and Local Potentials 2.3 The Effects of Stimulus Amplitude and Duration. 2.4 Induction of Action Potential Sequences 2.5 How to get a New Neuron? 3. Basic VOLTAGE-CLAMP Experiments 3.1 Capacitive and Voltage-dependent Currents 3.2 RC-Compensation 3.3 Inward and outward currents. 3.4 Changed command potentials. 3.5 I-V-Curves and “Reversal Potential” 3.6 Reversal Potentials 3.7 Tail Currents 4. The Neuron Editor 5. Pre-Settings 2 SimNeuron Tutorial 1. Lab Design We have kept the screen design as simple as possible for easy accessible voltage- and current-clamp experiments, not so much focusing on technical details of experimentation but on a thorough understanding of neuronal excitability in comparison of current-clamp and voltage-clamp recordings. The Current-Clamp lab and Voltage-Clamp lab are organized in the same way. On the left hand side, there is a selection box of the already available neurons with several control buttons for your recordings, including a schematic drawing the experimental set-up. The main part of the screen (on the right) is reserved for the diagrams where stimuli can be set and recordings will be displayed. Initially, you will be in the Current-Clamp mode where you will only see a current-pulse (in red) in the lower diagram while the upper diagram should be empty. Entering the Voltage-Clamp mode you will find a voltage-pulse in the upper diagram (in blue) with an empty lower diagram.