Multiple implants do not aggravate the tissue reaction in rat brain

PLoS One. 2012;7(10):e47509. doi: 10.1371/journal.pone.0047509. Epub 2012 Oct 16.

Abstract

Chronically implanted microelectrodes are an invaluable tool for neuroscientific research, allowing long term recordings in awake and behaving animals. It is known that all such electrodes will evoke a tissue reaction affected by its' size, shape, surface structure, fixation mode and implantation method. However, the possible correlation between tissue reactions and the number of implanted electrodes is not clear. We implanted multiple wire bundles into the brain of rats and studied the correlation between the astrocytic and microglial reaction and the positioning of the electrode in relation to surrounding electrodes. We found that an electrode implanted in the middle of a row of implants is surrounded by a significantly smaller astrocytic scar than single ones. This possible interaction was only seen between implants within the same hemisphere, no interaction with the contralateral hemisphere was found. More importantly, we found no aggravation of tissue reactions as a result of a larger number of implants. These results highlight the possibility of implanting multiple electrodes without aggravating the glial scar surrounding each implant.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Astrocytes
  • Brain / pathology*
  • Cicatrix
  • Electrodes, Implanted / adverse effects*
  • Female
  • Male
  • Microelectrodes*
  • Microglia
  • Rats

Grants and funding

This work was funded by the Knut and Alice Wallenberg foundation and by a Linneaus grant #600012701 from the Swedish Research Council and the Medical Faculty, Lund University. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.