Neurochemical Research

, Volume 24, Issue 1, pp 33–36 | Cite as

Stimulation of Immunoreactive Insulin Release by Glucose in Rat Brain Synaptosomes

  • Maria S. Santos
  • Emilia M. Pereira
  • Arsélio P. Carvaho


The effect of glucose on the release of immunoreactive insulin (IRI) in synaptosomes isolated from rat brain was studied. In the absence of glucose synaptosomes release about 4% (0.77 μIU/mg protein) of total content. Glucose increases significantly the IRI released by synaptosomes. Addition of the glycolytic inhibitor iodoacetic acid (IAA), decreased the glucose-induced release of IRI by about 50%, suggesting that glucose metabolism is involved. The observation that glucose provides a concentration related signal for IRI release indicates that this synaptosomal preparation may be useful as a model for research on the mechanism of insulin release in brain.

Synaptosomes glucose brain insulin insulin release 


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Copyright information

© Plenum Publishing Corporation 1999

Authors and Affiliations

  • Maria S. Santos
    • 1
  • Emilia M. Pereira
    • 2
  • Arsélio P. Carvaho
    • 1
  1. 1.Center for Neurosciences of Coimbra, Department of Zoology. M. S. Santos, Center for Neurosciences of Coimbra, Department of ZoologyUniversity of CoimbraCoimbraPortugal
  2. 2.Faculty of MedicineUniversity of CoimbraCoimbraPortugal

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