Journal of Biological Physics

, Volume 34, Issue 3–4, pp 441–457 | Cite as

Giant Glial Cell: New Insight Through Mechanism-Based Modeling

  • D. E. Postnov
  • L. S. Ryazanova
  • N. A. Brazhe
  • A. R. Brazhe
  • G. V. Maximov
  • E. Mosekilde
  • O. V. SosnovtsevaEmail author
Original Paper


The paper describes a detailed mechanism-based model of a tripartite synapse consisting of P- and R-neurons together with a giant glial cell in the ganglia of the medical leech (Hirudo medicinalis), which is a useful object for experimental studies in situ. We describe the two main pathways of the glial cell activation: (1) via IP3 production and Ca2 +  release from the endoplasmic reticulum and (2) via increase of the extracellular potassium concentration, glia depolarization, and opening of voltage-dependent Ca2 +  channels. We suggest that the second pathway is the more significant for establishing the positive feedback in glutamate release that is critical for the self-sustained activity of the postsynaptic neuron. This mechanism differs from the mechanisms of the astrocyte-neuron signaling previously reported.


Tripartite synapse Glia Neuron Modeling 



This work was partly supported by the European Union through the Network of Excellence BioSim (contract no. LSHB-CT-2004-005137). N. B. and A. B. acknowledge support from Lundbeck foundation. O. S. acknowledges support from Forskningsrådet for Natur og Univers (Skou stipendium). We are grateful to Ljudmila Erokhova for useful discussions.


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Copyright information

© Springer Science + Business Media B.V. 2008

Authors and Affiliations

  • D. E. Postnov
    • 1
  • L. S. Ryazanova
    • 1
  • N. A. Brazhe
    • 2
    • 3
  • A. R. Brazhe
    • 2
    • 3
  • G. V. Maximov
    • 2
  • E. Mosekilde
    • 3
  • O. V. Sosnovtseva
    • 3
    Email author
  1. 1.Physics DepartmentSaratov State UniversitySaratovRussia
  2. 2.Biophysics Department, Biological FacultyMoscow State UniversityMoscowRussia
  3. 3.Department of PhysicsTechnical University of DenmarkKongens LyngbyDenmark

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