Recording and Analyzing Synaptic Currents and Synaptic Potentials

Laurence Trussell1

1 Oregon Health Sciences University, Portland, Oregon
Publication Name:  Current Protocols in Neuroscience
Unit Number:  Unit 6.10
DOI:  10.1002/0471142301.ns0610s07
Online Posting Date:  May, 2001
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Abstract

Intracellular recording of synaptic currents (PSCs) under voltage clamp conditions provides the most accurate and direct means for measuring the earliest effects of neurotransmitters. With this tool, combined with pharmacological or ionic manipulations, one can obtain information about the type of transmitter used at a synapse, the dynamics of transmitterā€receptor interactions, the types and numbers of receptors activated, the effects of drugs on transmission, functional neural circuitry, and indications about the mechanisms of synaptic plasticity. Each synaptic current or potential is a reflection of many experimental variables: the ionic composition of the solutions, the temperature, the presence of pharmacological agents, the rate of synaptic stimulation, the history of stimulation, the variables of the recording system, as well as other factors unique to each preparation. Correct analysis of data requires all these parameters be considered. Both stimulusā€evoked and spontaneous synaptic events are covered in this unit since conclusions about synaptic and drug mechanisms are strongest when based upon recording of both types of activity. This unit outlines basic considerations for recording PSCs and PSPs in addition to guidelines for data analysis.

     
 
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Table of Contents

  • Recording and Analyzing Synaptic Currents and Synaptic Potentials
  • Strategic Planning
  • Basic Protocol 1: Recording Synaptic Events in Brain Slices
  • Commentary
  • Literature Cited
  • Figures
  • Tables
     
 
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Materials

Basic Protocol 1: Recording Synaptic Events in Brain Slices

  Materials
  • Tissue slice maintained in chamber with standard Ringers solution (see units 6.4 & 6.5)
  • External and patch‐pipet solutions (see Critical Parameters)
  • Test compound (e.g., Research Biochemicals, Tocris Cookson)
  • Recording solution with selective ion‐channel blockers (see Commentary)
  • Electrophysiology setup for patch‐clamp (see Table 97.80.4711 and units 6.1, 6.2, & 6.6)
  • Tape recorders (VCR with PCM adapter, DAT drive, or audio recorder)
  • Patch pipets (see units 6.3, 6.6, & 6.7)
  • Stimulus pipets (see Critical Parameters)
  • Stimulus isolators (AMPI; distributed in the U.S. by Pacer Scientific or Grass Instruments)
  • Acquisition/analysis hardware and software: pCLAMP, AxoBasic, AxoGraph (Axon Instruments) or CDR (Strathclyde Software)
  • Plotting/curve‐fitting software: Origin 5.0 (Microcal Software) or Igor (WaveMetrics)
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Figures

Videos

Literature Cited

Literature Cited
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