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Determination of CO2 Production in Subcellular Preparations Like Synaptosomes and Isolated Mitochondria Using 14C-Labeled Substrates and Radioactive CO2 Measurements

  • Mary C. McKennaEmail author
  • Irene B. Hopkins
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Part of the Neuromethods book series (NM, volume 90)

Abstract

The rate of 14CO2 production from 14C-labeled substrates is an indication of how actively the substrate is used for energy production by that tissue. This chapter focuses on the methods for determining the rates of 14CO2 production from freshly isolated synaptosomes and mitochondria from brain. The techniques for the isolation of synaptosomes from different age rat and/or mouse brain, and for the isolation of mitochondria are described in detail. Information is provided about how to set up the experiments for determining the rate of 14CO2 production (oxidation) from 14C-labeled substrates. Detailed information is given on performing the experiments and calculating the data. The techniques for performing substrate competition studies are also given. This chapter provides straightforward information about the useful techniques of determining the rates of 14CO2 production from any labeled 14C-substrate used by the brain for energy production. This technique can provide valuable information about substrate use in synaptosomes and mitochondria isolated from normal and/or abnormal brain.

Key words

Oxidation 14CO2 release Substrate competition Substrate metabolism Subcellular fractionation Synaptosomes Mitochondria Radioisotopes 

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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  1. 1.Department of Pediatrics and Program in NeuroscienceUniversity of Maryland School of MedicineBaltimoreUSA

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