Neurochemical Research

, Volume 13, Issue 6, pp 535–538 | Cite as

Effects of neuroleptics on glutaminase from rat synaptosomes

  • A. D. Sherman
  • M. Hamrah
  • J. Mott
Original Articles


Phosphate-activated glutaminase was isolated from synaptosomes from three areas of rat brain. Glutamine utilization phosphate activation and inhibition by glutamate or ammonia were assessed in the absence or presence of haloperidol, chlorpromazine, or clozapine. All three drugs (at 1 micromolar concentration) elevated theKm for glutamine using preparations from the amygdala, hippocampus, or striatum. They interfered with phosphate activation only in the amygdala preparation. No drug affected end-product inhibition. The data suggest that neuroleptics may depress the release of glutamic acid from synaptosomes by interfering with the activation of glutaminase by phosphate.

Key Words

Neuroleptics glutaminase synaptosomes 


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Copyright information

© Plenum Publishing Corporation 1988

Authors and Affiliations

  • A. D. Sherman
    • 1
  • M. Hamrah
    • 1
  • J. Mott
    • 1
  1. 1.Neurochemical Research Laboratory, Department of PsychiatryUniversity of IowaIowa City

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