Neurochemical Research

, Volume 6, Issue 11, pp 1193–1203 | Cite as

Sedimentation and release properties of P2 fractions derived from rat cerebral cortex slices incubated with radiolabeled GABA for a short or long time period

  • E. A. Singer
  • W. Sieghart
  • P. Placheta
Original Articles


On homogenization of rat cerebral cortex slices previously incubated with [3H] GABA or [14C]GABA for 5 or 30 min, respectively, particles were recovered in P2 fractions which exhibited similar buoyant density, but different sedimentation velocity on linear sucrose density gradient centrifugation. The K+-evoked release of [3H]GABA from particles isolated from slices previously incubated for 5 min with [3H]GABA was increased in the presence of exogenous Ca2+. In contrast, the K+-evoked release from particles isolated from slices previously incubated for 30 min with [3H]GABA, was not influenced by the presence of exogenous Ca2+.

These results suggest that, depending on the incubation time of slices, exogenously applied GABA can be detected in differnnt pools. These pools not only seem to differ in their Ca2+ dependency of K+-evoked release but also in their subcellular localization.


Sucrose Cerebral Cortex Incubation Time Subcellular Localization Density Gradient 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Plenum Publishing Corporation 1981

Authors and Affiliations

  • E. A. Singer
    • 1
  • W. Sieghart
    • 2
  • P. Placheta
    • 1
  1. 1.Institute of PharmacologyUniversity of ViennaViennaAustria
  2. 2.Department of Biochemical Psychiatry Psychiatrische UniversitätsklinikUniversity of ViennaAustria

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