Synaptic Modifications and Memory von Leon L. Voronin | An Electrophysiological Analysis | ISBN 9783642476150

Synaptic Modifications and Memory

An Electrophysiological Analysis

von Leon L. Voronin
Buchcover Synaptic Modifications and Memory | Leon L. Voronin | EAN 9783642476150 | ISBN 3-642-47615-5 | ISBN 978-3-642-47615-0

Synaptic Modifications and Memory

An Electrophysiological Analysis

von Leon L. Voronin

Inhaltsverzeichnis

  • 1 Hippocampal Long-Term Potentiation and Its Characteristics.
  • 1.1 Brief Overview of the Structure of the Hippocampus.
  • 1.2 Electrical Responses of the Hippocampus.
  • 1.3 Initial Experiments on Long-Term Potentiation.
  • 1.4 Working Hypothesis and Early Results.
  • 1.5 Methods.
  • 1.6 Long-Term Potentiation of Field Potentials in the CA3 and CAI Regions.
  • 1.7 Low-Frequency Depression and Self-Restoration of the Potentiated Response.
  • 1.8 Specificity of Long-Term Potentiation for the Tetanized Input.
  • 1.9 Involvement of Reinforcing Systems During Tetanization.
  • 1.10 Discussion.
  • 1.11 Summary.
  • 2 Unitary and Minimal Postsynaptic Potentials (Literature Review).
  • 2.1 Introduction.
  • 2.2 Methods Related to Unitary and Minimal PSP Recording.
  • 2.2.1 Intracellular Stimulation of the Afferent Unit.
  • 2.2.2 Macrostimulation of Afferent Fibres.
  • 2.2.3 Intracerebral Microstimulation.
  • 2.2.4 Recording of “Minimal” PSPs.
  • 2.2.5 Additional Procedures for the Detection of Single UPSPs.
  • 2.2.6 Measurements of UPSPs and MPSPs Amplitudes and PSCs.
  • 2.2.7 Mono- and Polysynaptic UPSPs.
  • 2.3 Unitary Field Potentials — “EEG Quanta”.
  • 2.4 Applications of Unitary and Minimal PSP Recordings.
  • 2.4.1 Organization of Neuronal Connections.
  • 2.4.2 Electrical and Chemical Synapses in the CNS.
  • 2.4.3 Spatial Organization of Synapses on the Somadendritic Membrane.
  • 2.5 Studies of Synaptic Plasticity in the CNS.
  • 2.5.1 Introductory Remarks.
  • 2.5.2 Habituation and Sensitization in Invertebrate CNSs.
  • 2.5.3 Conditioning Mechanisms in the Aplysia CNS.
  • 2.5.4 LFD in the Vertebrate CNS.
  • 2.6 Conclusions.
  • 2.7 Summary.
  • 3 “Minimal” Field Potentials of the Hippocampus and Their Post-Tetanic Changes.
  • 3.1 Introduction.
  • 3.2 Methods.
  • 3.3 Field Potentials Correlated with Neuronal Discharges from theContralateral Hippocampus.
  • 3.4 Field Activity After Spikes of the Schaffer Collaterals.
  • 3.5 Minimal Field Potentials.
  • 3.6 Post-Tetanic Changes of Minimal FPs.
  • 3.7 Discussion.
  • 3.8 Summary.
  • 4 Excitatory Postsynaptic Potentials of Hippocampal Neurones and Their Low-Frequency Depression.
  • 4.1 Introduction.
  • 4.2 Methods.
  • 4.3 Responses to Single Stimuli.
  • 4.4 Responses to Paired Stimuli of Different Amplitudes.
  • 4.5 Changes of EPSPs During Low-Frequency Stimulation.
  • 4.6 Changes of IPSPs During Low-Frequency Stimulation.
  • 4.7 Discussion.
  • 4.8 Summary.
  • 5 Responses of Hippocampal Neurones During Long-Term Potentiation.
  • 5.1 Introduction.
  • 5.2 Methods.
  • 5.3 General Description of Neuronal Responses.
  • 5.4 Short-Term Post-Tetanic Changes.
  • 5.5 Long-Term Changes in Spike Responses after Tetanization.
  • 5.6 Post-Tetanic Changes of Postsynaptic Potentials.
  • 5.7 Post-Tetanic Changes in Excitability and Resting Membrane Potential.
  • 5.8 Discussion.
  • 5.9 Summary.
  • 6 Changes in Acetylcholine Sensitivity During Long-Term Potentiation.
  • 6.1 Introduction.
  • 6.2 Effects of Acetylcholine Iontophoresis on Cellular and Field Responses.
  • 6.3 Changes in ACh Sensitivity During LTP.
  • 6.4 Discussion.
  • 6.5 Summary.
  • 7 Quantal Analysis of Postsynaptic Potentials (Literature Review).
  • 7.1 Introduction.
  • 7.2 Principles of the Quantum Hypothesis.
  • 7.3 Methods of Determination of the Mean Quantal Content.
  • 7.3.1 Direct Counting of Quantal Contents of Single PSPs.
  • 7.3.2 The Method of “Miniatures”.
  • 7.3.3 Histogram Method.
  • 7.3.4 Method of Failures.
  • 7.3.5 Method of the Coefficient of Variation.
  • 7.3.6 Analysis of Dispersions.
  • 7.3.7 Deconvolution Technique.
  • 7.3.8 Other Methods.
  • 7.4 Corrections for the Methods of Estimating m.
  • 7.4.1 Non-Linear Summation.
  • 7.4.2 Control of Steady State.
  • 7.4.3“Non-Specific” Activity.
  • 7.4.4 Multicomponent Miniature PSPs.
  • 7.4.5 Additional Remarks.
  • 7.5 Poisson and Binomial Distributions of PSP Amplitudes.
  • 7.6 Methods of Estimating Binomial Parameter p.
  • 7.6.1 Variance of Quantal Distribution.
  • 7.6.2 Variances of Amplitudes of PSPs and mPSPs.
  • 7.6.3 Division of Amplitude Histogram According to µ.
  • 7.6.4 Automatic Computation when v Is Known.
  • 7.6.5 Automatic Analysis of Amplitude Distributions.
  • 7.6.6 Combination of Variance and Failures Methods.
  • 7.6.7 Other Methods.
  • 7.7 Additional Explanations to Methods of Computing Quantal Parameters.
  • 7.7.1 Non-Stationarity and Non-Uniformity.
  • 7.7.2 Models with Non-Uniform p.
  • 7.7.3 Other Modifications.
  • 7.8 Basic Quantal Parameters for Various Junctions.
  • 7.8.1 Neuromuscular Junctions and Autonomic Ganglia.
  • 7.8.2 Invertebrate CNS.
  • 7.8.3 Spinal Cord.
  • 7.8.4 Cerebrum.
  • 7.8.5 Hippocampus.
  • 7.9 Binomial Parameters n and p for Various Junctions.
  • 7.9.1 Neuromuscular Junctions and Autonomic Ganglia.
  • 7.9.2 Invertebrate CNS.
  • 7.9.3 Spinal Cord.
  • 7.9.4 Cerebrum.
  • 7.10 Quantal Analysis of Synaptic Plasticity.
  • 7.10.1 Various Applications of Quantal Analysis.
  • 7.10.2 Frequency Facilitation (FF).
  • 7.10.3 Frequency Depression (FD).
  • 7.10.4 Post-Tetanic Potentiation (PTP) and Heterosynaptic Facilitation (HSF).
  • 7.10.5 Long-Term Facilitation (LTF).
  • 7.11 Conclusions.
  • 7.12 Summary.
  • 8 Application of Quantal Analysis to Central Synapses.
  • 8.1 Introduction.
  • 8.2 Methods.
  • 8.3 Consideration of Known Methods of Determination of Quantal Parameters.
  • 8.4 The Histogram Method.
  • 8.5 Method Based on the Ratio of the Mean to Maximal Amplitude.
  • 8.6 Quantal Parameters of Unitary EPSPs of Snail CNS.
  • 8.7 Theoretical Distributions of PSP Amplitudes.
  • 8.8 Discussion.
  • 8.9 Summary.
  • 9 Models ofTransmitter Depletion and Their Application to Analysis of Synaptic Plasticity (Literature Review).
  • 9.1 Introduction.
  • 9.2 Basic Model Parameters and Recording Conditions.
  • 9.3 Model of Transmitter Depletion Without Mobilization.
  • 9.3.1 Method of Paired Stimulation.
  • 9.3.2 Method of Amplitude Dependence on Serial Stimulus Number During Frequency Stimulation.
  • 9.3.3 Method of Relationship Between Amplitude and Sum of Amplitudes of Previous Responses.
  • 9.4 Model of Transmitter Depletion with Mobilization.
  • 9.4.1 Restoration after Stimulation Method of Paired Stimulation.
  • 9.4.2 Frequency Stimulation. “Continuous” Model.
  • 9.4.3 Approximate Estimates of Parameters of the Continuous Model.
  • 9.4.4 Frequency Stimulation. “Discrete” Model.
  • 9.5 Modifications of the Depletion Model for Variable F.
  • 9.5.1 Model of “Partial Depletion”.
  • 9.5.2 “Partial Depletion” with Paired Stimulation.
  • 9.6 Transmitter Mobilization and Parameters of the Store Pool.
  • 9.6.1 Relationship Between Mobilization and Stimulus Frequency.
  • 9.6.2 Dependence of Mobilization on Time.
  • 9.6.3 Total Transmitter Store.
  • 9.7 Depletion Model in Studies of Synaptic Plasticity.
  • 9.7.1 Applications of the Depletion Model and Simple Synaptic Plasticities.
  • 9.7.2 Frequency Depression and Postactivation Depression.
  • 9.7.3 Postactivation Facilitation.
  • 9.7.4 Frequency Facilitation.
  • 9.7.5 Post-Tetanic Potentiation.
  • 9.8 Conclusion.
  • 9.9 Summary.
  • 10 Parameters of Transmitter Depletion Model for Snail Central Synapses and Comparison of Depletion and Quantal Models.
  • 10.1 Introduction.
  • 10.2 Discrete Model of “Partial” Transmitter Depletion.
  • 10.3 Discrete Model with Arbitrary Changes in F.
  • 10.4 EPSP Changes During Stimulation.
  • 10.5 Calculation of Parameters by Basic Methods of the Depletion Model.
  • 10.6 Calculation of Parameters by Method 10.3.
  • 10.7 Comparison of Parameters of Depletion and Quantal Models.
  • 10.8 Discussion.
  • 10.9 Summary.
  • 11 Quantal Analysis of Short-Term Plasticities at Central Synapses.
  • 11.1 Introduction.
  • 11.2 Paired-Pulse Facilitation of Hippocampal Responses.
  • 11.3 Low-Frequency Depression of Hippocampal Responses.
  • 11.4 Low-Frequency Depression at Snail Central Synapses.
  • 11.5 Paired-Pulse Facilitation in Hippocampal Slices.
  • 11.6 Discussion.
  • 11.7 Summary.
  • 12 Quantal Analysis of Hippocampal Long-Term Potentiation in Vivo.
  • 12.1 Introduction.
  • 12.2 Methods.
  • 12.3 Unitary Postsynaptic Potentials of Hippocampal Neurones.
  • 12.4 Post-Tetanic Changes in Postsynaptic Potentials Evoked by Microstimulation.
  • 12.5 Statistical Analysis of Minimal EPSPs Evoked by Microstimulation.
  • 12.6 Changes in Quantal Parameters After Tetanization.
  • 12.7 Discussion.
  • 12.8 Summary.
  • 13 Quantal Analysis of Minimal Postsynaptic Potentials in Hippocampal Slices: Binomial Model.
  • 13.1 Introduction.
  • 13.2 Methods.
  • 13.3 Results of Computer Simulations.
  • 13.3.1 Testing Different Methods.
  • 13.3.2 Testing Methods of p Determination.
  • 13.3.3 Testing “Objective” Method of Failures Determination.
  • 13.4 Results of Physiological Experiments.
  • 13.4.1 General Description.
  • 13.4.2 Testing EPSP Amplitude Stability.
  • 13.4.3 Comparison of Parameters Calculated from Different Samples.
  • 13.4.4 Objective vs. Subjective Method of Failures Determination.
  • 13.4.5 Comparison of Different Methods.
  • 13.4.6 Optimization of Noise Standard Deviation.
  • 13.4.7 Mean Quantal Parameters of Hippocampal Synapses.
  • 13.5 Discussion.
  • 13.5.1 Simulation Experiments.
  • 13.5.2 EPSP Measurements and Noise Reduction.
  • 13.5.3 Testing Procedures and Sample Sizes.
  • 13.5.4 Applicability of the QuantumHypothesis and Simple Binomial Model.
  • 13.5.5 Noise Reduction During EPSP.
  • 13.5.6 Quantal Parameters of Hippocampal Synapses.
  • 13.6 Summary.
  • 14 Binomial Analysis of Long-Term Potentiation of Minimal EPSPs in Hippocampal Slices.
  • 14.1 Introduction.
  • 14.2 Methods.
  • 14.3 Results.
  • 14.3.1 Long-Term Potentiation of Minimal EPSPs.
  • 14.3.2 Estimates of Quantal Parameters.
  • 14.3.3 Post-Tetanic Changes in Mean Quantal Content.
  • 14.3.4 Post-Tetanic Changes in Quantal Size.
  • 14.3.5 Post-Tetanic Changes in Binomial Parameters.
  • 14.3.6 Differential Changes in m and v for Different LTP Magnitudes.
  • 14.4 Discussion.
  • 14.5 Summary.
  • 15 Analysis of Fluctuations of Minimal EPSPs in Vitro: Quantal Model.
  • 15.1 Introduction.
  • 15.2 Methods.
  • 15.3 Results of Simulation Experiments.
  • 15.4 Results of Physiological Experiments.
  • 15.5 Discussion.
  • 15.5.1 Reliability of the Deconvolution Procedure.
  • 15.5.2 Post-Tetanic Changes in Quantal Parameters.
  • 15.5.3 Differential Changes in Quantal Parameters at Different LTP Magnitudes.
  • 15.5.4 Two Types of Synaptic Mechanisms of LTP Maintenance.
  • 15.6 Summary.
  • General Conclusions.
  • References.