Skip to main content
  • Poster presentation
  • Open access
  • Published:

Modeling the effects of neuronal morphology on dendritic chloride diffusion and GABAergic inhibition

Gamma-aminobutyric acid receptors (GABAARs) are ligand-gated chloride (Cl−) channels which mediate the majority of inhibitory neurotransmission in the CNS. Spatiotemporal changes of intracellular Cl− concentration alter the concentration gradient for Cl− across the neuronal membrane and thus affect the current flow through GABAARs and the efficacy of GABAergic inhibition. However, the impact of complex neuronal morphology on Cl− diffusion and the redistribution of intracellular Cl− is not well understood. Recently, computational models for Cl− diffusion and GABAAR-mediated inhibition in realistic neuronal morphologies became available [1–3]. Here we have used computational models of morphologically complex dendrites to test the effects of spines on Cl− diffusion. In all dendritic morphologies tested, spines slowed down longitudinal Cl− diffusion along dendrites and decreased the amount and spatial spread of synaptically evoked Cl− changes. Spine densities of 2-10 spines/µm decreased the longitudinal diffusion coefficient of Cl− to 80-30% of its value in smooth dendrites, respectively. These results suggest that spines are able to limit short-term ionic plasticity [4] at dendritic GABAergic synapses.

References

  1. Jedlicka P, Deller T, Gutkin BS, Backus KH: Activity-dependent intracellular chloride accumulation and diffusion controls GABAA receptor-mediated synaptic transmission. Hippocampus. 2011, 21: 885-898.

    CAS  PubMed  Google Scholar 

  2. Doyon N, Prescott SA, Castonguay A, Godin AG, Kröger H, Koninck YD: Efficacy of synaptic inhibition depends on multiple, dynamically interacting mechanisms implicated in chloride homeostasis. PLoS Comput Biol. 2011, 7 (9): e1002149-10.1371/journal.pcbi.1002149.

    Article  PubMed Central  CAS  PubMed  Google Scholar 

  3. Lewin N, Aksay E, Clancy CE: Computational modeling reveals dendritic origins of GABAA-mediated excitation in CA1 pyramidal neurons. PLoS One. 2012, 7 (10): e47250-10.1371/journal.pone.0047250.

    Article  PubMed Central  CAS  PubMed  Google Scholar 

  4. Raimondo JV, Markram H, Akerman CJ: Short-term ionic plasticity at GABAergic synapses. Front Syn Neurosci. 2012, 4: 5-10.3389/fnsyn.2012.00005.

    Article  CAS  Google Scholar 

Download references

Acknowledgements

Supported by the NSF/BMBF (US-German Collaboration in Computational Neuroscience, No. 01GQ1203A).

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Namrata Mohapatra.

Rights and permissions

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Mohapatra, N., Santamaria, F. & Jedlicka, P. Modeling the effects of neuronal morphology on dendritic chloride diffusion and GABAergic inhibition. BMC Neurosci 15 (Suppl 1), P138 (2014). https://doi.org/10.1186/1471-2202-15-S1-P138

Download citation

  • Published:

  • DOI: https://doi.org/10.1186/1471-2202-15-S1-P138

Keywords