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

Abstract

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.

Keywords

Sucrose Cerebral Cortex Incubation Time Subcellular Localization Density Gradient 

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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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